Re: New Predator Tank Stocking, actually plumbing/overflow Advice   10/29/06
Thanks for all your advice Bob, where can I send your Christmas present??
<Mmm, the Red Cross?>
On the comments about my 'emergency drain' on my smaller tank.  I think perhaps you misread what I was getting at.  I already have a corner overflow with a drain out the bottom of my tank to my sump.  My water level in my overflow remains at approximately 3" during normal operation.  I am thinking of putting my emergency drain within the overflow compartment perhaps about 5" from the bottom of the overflow on the back or side of the glass.  If there was a power failure... Simply my pump would not continue to fill my tank and tank water would lower to the level of my overflow draining out the bottom drain.  It wouldn't have any effect on the emergency bulkhead drain.  The only instance in which the emergency bulkhead would come into play would be if the strainer on the primary bulkhead drain would become clogged thus allowing the overflow water to rise beyond 5" and then the water would have the same drainage capacity as my primary overflow.
<Ah, I see now>
Correct?  Two 1 1/4" drains on a 90 gallon tank should be sufficient since my primary drain already easily handles the tank flow?
<Yes>
On my 200gallon tank, which is becoming the predator tank I described below, I only have the one drain and my pump that would be rated at 1,775gph overflows the overflow and raises the tank water and runs my sump dry.  Thank god I did a trial run on freshwater and nothing else is in the tank.  I've emptied my freshwater and someone's coming out on Friday to drill a second 1 1/2" drain on this tank.
<I'd have multiple... oh, I see this addressed below>
I'm wondering though, If my existing drain is not sufficient to handle the water flow, adding a second drain would handle the water inflow... But if either one of them becomes clogged... My sump will run dry.  I was so paranoid of my 200 gallon tank overflowing and flooding my developed basement... I made it virtually impossible to overflow my tank... Pretty much in every instance my sump will run dry long before my tank overflows.  Is it better to add as second hole within the existing overflow several inches up the back of it?
<I'd keep at the same level.>
  Should I possibly add another overflow box within the tank and add a third drain?  i.e. one overflow contains two drains and the other overflow contains one drain?
<Yes>
3 drains total and obviously the highest positioned drain serving as my emergency drain?
Dave
<A good plan. BobF>

Marine Plumbing, drains/overflows...  10/24/06
     Hey there, I mailed you quite a while with a question on waterproofing a homemade sump. Thanks for the advice you gave me, it worked out well if you remember.. I was thinking about getting my sump rhino lined.. yes it sounds dumb now).
<Actually... polyethylene... just expensive in HI>
Anyway, I was hopping you would be able to give me a little more of that great advice. I did lots of searching on your site but its a little hard to find the right search words.. all the wrong topics keep coming up. So, the problem... I currently have a 240gal 24x24x96 tank. My drain lines cannot handle the amount of water my pump is putting into the tank.
<... not unusual a situation>
I have two 1.5" drains with Durso style standpipes in the overflow boxes. The pump is the SUPER quiet sequence dart. The pump is pushing water up through about 6 feet of head, which according to the pumps flow charts should be giving me somewhere near 2400gph. Now a 1.5" drain should give me 60gpm right ?
<Mmm, no... not in the real world>
(I got that on your site with another person you helped out) Then two 1.5" drains should give me 120 gpm or 7200gph. Now considering that my pump is pumping out at around 2400gph I know I have a design flaw. Even if the pump had no head its max output is rated at 3600 gph which is still way under what my overflows should be able to do. So here it goes, ill start with the left side overflow and run you down the pipes.
     The standpipes drains about 1" below the waterline. The water then falls down about 20" to the bulkhead. Under the tank I have a union placed right up against the bottom of the bulkhead. After the union the water falls 6" down to a 45elbow then travels 6" horizontally to another 45elbow, through a bulkhead with another 45elbow sending the water falling 15" or so to a submerged output. I'm going to be putting a micron bag on this line. The submerging keeps it nice and quiet.
<Yes>
     The overflow on the right is identical until you get past the union on the underside of the tank. After that union the water drops about 6" to a 45elbow then about 8" horizontally to another 45elbow sending it (still horizontally) to a tee. The tee has unions on both side and 45elbows going into two bulkheads for the two separate chambers of my wet/dry. To do something about the noise and the velocity of water tearing the blue filter pad to shreds) I have two small bowls that sit on the wet/dries blue filter, the bulkheads output are submerged in these bowls about 2".
<Good technique>
     So to sum it up, the left side has two bulkheads, one union and three 45elbows to a submerged output. The right side has 3 bulkheads( two are on separate lines after the tee) four 45elbows ( two on separate lines after the tee) three unions, and one tee, going into a submerged output ( really didn't mean for this to start sounding like a riddle hehe). All the plumbing is in 1.5" and I though that maybe the air holes at the top of the standpipes weren't big enough.
<Mmmm...>
So I took the tops off  and let the noise all out. It still nearly overflowed my tank. Could it be that my standpipes need more head pressure to deliver more flow?
<No/pe>
should I try to lower them?
<Won't help much... not appreciably>
Or could it be that having both my lines submerged has left the air nowhere to go but up making it hard for water to go down? I don't know but, Am hopping you do.
<No more hopping/hoping...>
     The last time you gave me advice you mentioned you have a home on the big island.
<Yes, in Holualoa... on the 180... just down from K. Komo market>
I hope you weren't there for the quake and your house is ok. anyway... hoping for some good advice over on Oahu.. take care
<Thank you... What you "really" need are more and or larger overflows... two, make that three 2" inside diameter... the rest of the plumbing configuration detailed is fine... not contributing to your lack of flow potential... Either re-drilling the tank and re-doing the plumbing or changing the delivered water to the main tank (a smaller pump, diverting part of the flow... a restriction valve...) are your easy alternatives. A hui ho! Bob Fenner in Thailand>
Mahalo nui loa -Chris

R2: Hard Plumbing...Soft Plumbing...Pump Intakes...Bulkheads - 10/20/06
Hi Eric,
<<Hello Ken>>
Thanks again.
<<Always welcome>>
Few more questions if it is ok?
<<Sure>>
What do you suggest that I use from my 1" bulkhead return to my sump in terms of piping or tubing.  The bulkhead is pretty much right on top of the sump.  Do I use PVC straight down, or angle it somewhat, or tubing.
<<I would use rigid PVC straight in to the sump with a 45-degree ell on the end positioned just below the water's surface.  The ell helps to clear bubbles so they aren't trying to go back up the pipe/creating resistance like a "straight-in shot" would>>
I am asking the question based on what may be the quietest with the standpipe in the tank.
<<Understood>>
I thought I read somewhere that straight down was not the best option.
<<Thus the reason for the ell/for placing the output below the surface>>
When I fill the tank with water the first time and run the system to check for leaks:
A) Can I keep this water and go with it or do I need to change it due to new tank, tubing, piping, etc.
<<Should be fine to "keep">>
I was wondering if there is anything that could be bad for the live rock or livestock once I stock the tank?
<<Mmm...be sure to follow proper cycling protocol for newly established systems>>
B) How long can I run the system without lighting (except room lighting) without putting anything into the tank?
<<Theoretically speaking...indefinitely...but I like to put light on my rock while curing/cycling the tank, and let the natural algae progression take its course>>
I was wondering if I would get algae if I ran it for a couple of three days with nothing in it, as I am not sure what day I am getting my rock.
<<No matter...will happen eventually>>
I used to use Reef Crystals many years ago when I had a reef tank. Is this still good?
<<Will be fine>>
My tank is 90 gallons with a Marine Technical Concepts HSA-1000 skimmer, and their Pro-Cal calcium reactor, Maristar HQI (2x250 watts) and T5 (2x54 watts), and two Tunze Turbelle Stream 6000's with controller.  How many pounds of live rock do I need?
<<I like to go with a "bit less" than most would suggest for reasons of aesthetics/giving the organisms room to move around/grow.  I would start with about 60lbs of a premium rock and make adjustments as need from there>>
Is it 1.5 lbs per gallon or less than that?
<<A useless measurement in my opinion...to many variables (weight of the rock, type system/ancillary equipment employed, species/type animals, etc.)>>
It is supposed to be Fiji.
<<Should be fine...though some regard this rock as "bargain" rock>>
It is from LFS and it is as cured as you are going to see from a store.
<<I would still expect/allow for this in your tank...albeit likely diminished>>
I will also use the packaged live sand too (for aesthetics mostly), maybe about 3/4" or so (depth ok?).
<<Yes>>
Is the Carib-Sea live sand or the Nature's Ocean a better choice?
<<Waste of money in my opinion...use dry aragonite and let the rock seed the sand>>
Is there a certain grain size that I should be using, and do I have to put this under the rock or can I put the rock in the tank first, and then the sand up to it?
<<A mix of grades from sugar-size to 2mm is fine...and yes, for stability placing the rock on the tank bottom and then adding the sand works fine>>
I think I used up my quota of questions.  Thank you so much for your help.
<<No worries mate...we're here to help>>
Regards,
Ken
<<Be chatting.  Eric Russell>>

Hard Plumbing... Soft Plumbing... Pump Intakes... Bulkheads - 10/19/06
Hi Eric,
<<Hello Ken>>
Thanks for the response.
<<Quite welcome>>
In between I sent you my email and saw your response I had discovered the world of flexible PVC.
<<Ah...>>
I used this with PVC glue.
<<Yep>>
I used 3/4" and 1" for my two pumps.  I did a smooth curve (not a loop).
<<Excellent>>
It probably took 15" -18" to make the smooth curve.  I would imagine that this should be ok?
<<Will be fine>>
Does this stuff definitely hold?
<<If you installed it correctly, yes...is as strong or stronger than schedule-40 PVC hard pipe>>
I also put a union on the suction side.  Is this ok?
<<Yes...and a good idea to facilitate maintenance of the pump>>
I figure that in case I ever have to take the pump out this would be the simplest.
<<Indeed>>
I would imagine that I should put a ball valve somewhere on the discharge side.  What do you think?
<<I agree, but not a ball-valve...instead install a "gate-valve" as this will give you a much finer control of the flow.  You should also consider placing a union between the pump-discharge and the gate-valve for the same reason you placed one on the intake side of the pump>>
I know some people would say put a valve on both ends of the pump due to sump drainage if the pump is removed but I could always take some PVC pipe and a 90 degree elbow and some more pipe and put it higher than the water line.
<<If this is your "return pump" it should not be an issue as you should have the sump plumbed in such a way as to hold all the transient water when the pump is off.  Thus, once you turn off the pump and allow the tank to drain down, water from the drain line/pump intake line wouldn't be a problem>>
I am trying to keep as many "add-ons" out of my plumbing.
<<Always good>>
Of course I need to lose some gph anyway since the pump is rated at 790 GPH at 5-feet of head and the tank can only handle 600 GPH.
<<No worries, the gate-valve will allow any final adjustment if necessary...and I think you will find that 600 GPH will be too much for the single 1" drain to handle easily>>
One more question about the standpipe with the Mega Flow.
<<Okay>>
Is this noisy?
<<Usually, yes...you will probably want to consider a modification.  Do a Google search re "Durso Standpipe" or "Stockman Standpipe"...I think both offer "kits" for these now>>
I was curious why I read about people switching to the Durso standpipe.  Do you have any ideas on this?
<<Indeed...most hobbyists find the "stock" standpipes supplied by the tank manufacturers to be about as inadequate as the throughputs themselves>>
Also, is there a trick to "tuning" either of these standpipes?
<<Should be listed on the respective websites, but generally, aspirating the drains sometimes proves helpful>>
Oh yea, and I did replace the two bulkheads that came with the tank.
<<Ah, very good>>
Thanks a lot.
Regards,
Ken
<<Pleased to share, EricR>>

Check valves and Overflow - 10/15/06
Hi there,
<Hi.>
I found your site after doing an exhaustive search for alternatives to Check-valves.  I have a 250 gallon tank with a classic wet-dry sump design with overflow boxes on each corner.  The problem is my return lines.   I have two ½" returns on the very bottom of the tank so there are no stand pipes to break the siphon. <You should consider building some. This is a very weak point in your setup. Try to visualize 250g of water on your floor.> Additionally, I have a ½" return that has a standpipe that runs up the left overflow box and then goes back down to 2 bulkheads that return the water to the tank, this one has a small tube that is supposed to break the siphon.  The same thing exists on the right side except it does not go back down to the bulk-heads through the return box its just a single ½" pipe that has t connectors to the two bulkheads and just ends at the top so there is no anti-siphon pipe at the top.  My question is:  Is there an alternative to completely changing the way water is returned to the tank or using un-dependable swing check-valves. <If there is, I'm not sure what it would be... check valves are about as reliable as they need to be but need to be inspected/tested at regular intervals.> I guess I could do check valves but will have to clean them every month and there is still the possibility they won't work. <If you clean them at this interval, then they will work for years. I use the dual-union style so that they are easy to take out of service for maintenance.> Any thoughts would be welcomed.
Thanks,
Jason B.
<Cheers, J -- >

Micro-Bubbles/Drain Line Plumbing - 10/14/06
I have a 215G Oceanic Reef-Ready that came as is from the factory.  I thought I did my homework and then some when ordering this tank, but I have since learned that the drains are inadequate for this size tank.
<<A common enough opinion/fact that you'd think the manufacturer would eventually "get it">>
Re-drilling this thing really is not an option at this point so I need to make best with the situation that I have.
<<Can be done, yes>>
I'm running 2 Mag-Drive 7's for my returns, I'm figuring that I'm pushing about 700-800gph combined with the 2 pumps after figuring in head pressure.
<<This should pretty much "max out" the 1" drains>>
I have two Vortec pumps to provide additional circulation within the aquarium.
<<Excellent>>
The two 1" drains are handling this with no real noise issues.
<<Good...often this is not the case>>
The problem I'm having is with micro-bubbles, I'm not sure if this would be related at all to the inadequate drains.
<<Could be/probably is...nowhere for the entrained air to go...>>
I'm doing a container with a container sump system using Rubbermaid Totes.  I figured that my problem was the result of not enough baffling, but I have since read the opinion of one of your crew members that micro-bubbles are not the result of the water returning from the drain, instead they are only formed in pressurized situations.
<<Hmm...>>
Is this fact, or just his opinion?
<<I have no wish to second-guess others of the Crew (especially without knowing the reasoning), but I suspect both (opinion based on some fact).  But that said, I don't agree that micro-bubbles would only be present in "pressurized situations."  As with the case of venturi-style skimmers, the bubbles can be the result of trapped air and water turbulence...in "my" opinion.  Maybe it comes down to the individual interpretations for "micro-bubbles," but I have witnessed some very fine bubbles emitting from drain lines over the years>>
I poured a glass of water in my tank and saw large bubbles near the surface and very fine bubbles deeper in the tank, similar to the micro-bubbles that I have.
<<Indeed...much the same as what is happening in your drain lines>>
If it is true then my problem must lie within my plumbing work or the pumps themselves.
<<Bingo!>>
I don't want to reconfigure my baffling setup if I'm not getting rid of the source.
<<Hmm...well...supposedly the "baffling" should handle any bubble issues (is why it is there), but excessive quantities of very small bubbles can be very difficult to "baffle out."  I agree with your stance to attach the source of the bubbles>>
I did the Vaseline test on all plumbing connections and that didn't seem to help.
<<Do be sure to clean the joints of any residual Vaseline to preclude possible deterioration of the plastic from the petroleum elements (Bob "cringes" at the use of this product).  It's likely the problem stems from the fact you have the drains pretty much at their maximum potential.  "Noise" isn't the only problem associated with overloaded drains.  I think your problem is entrained air due to the amount of water you're pushing through these 1" drains...aspirating the drains may provide relief.  This involves inserting small-diameter tubing at the highest point in the line to allow trapped air a route of escape.  The exact diameter and length of insertion requires a bit of experimentation>>
I have two 30G totes as my main sumps, linked together through bulkheads.  One was going to be a refugium.  I'm now thinking that perhaps I should now use the refugium tote to provide additional room for dealing with the micro-bubbles so I can have more containers and hence more baffling.
<<Mmm, I like the idea of the refugium.  I would look to aspirating the drain lines...you could also try using just one return pump to reduce flow in the drains (would still be plenty of flow through the sump/refugium in my opinion>>
I also seem to have what appears to be a bunch of fine particles in my saltwater, like dust in the air, only seen when turning the lights off and shining a light through the tank from one side and viewing from another.
<<Hmm, do you have a fine substrate?  Bioturbators?  I wouldn't be concerned>>
I'm sure after all the work I have been doing in an attempt to rid myself of the bubbles I have introduced a good bit of dust into the tank.  The tank was filled with purified water, so the source is not my source water.  But I'm not sure if this can be related in anyway to micro-bubble formation, or if everyone who did the same thing would see it in their tanks as well.   Can you tell me what would be the best way in using a sump system such as this to filter out these fine particles?
<<Some folks use filter socks on their returns.  I am not a fan of these as they trap detritus (obviously) and require constant maintenance/attention to keep them clean/become a source of decaying organics.  Personally, I wouldn't bother/worry about some particulates in the water>>
I have already drained this tank once, and it would take a lot to have to do so again.
<<I see no reason to drain the tank>>
Please let me know any input you can provide for my situation.
<<Have done so...>>
I hope this post is coherent; I have been up late trying to work this thing out.  but I'm determined to do so.
<<No doubt you will>>
Thanks,
Kevin
<<Regards, EricR>>

Plumbing/Overflow And Pump Size 10/6/06
Hello,
<Hello Wayne>
I am setting up a 35 gallon marine tank with a 20g sump. My question is what size overflow should I use since the tank is not drilled. I was planning on connecting a 1/10 hp chiller to the sump with the return to the main tank.  The chiller recommends a flow of 200-300 gph with 5/8in tube fittings. Would a CS50 overflow box be o.k. or should I go with the CS90. Also, what pump flow would you recommend.
<First, I would recommend nothing lower than a 400gph pump.  You will lose some gph through the chiller and the return line.  A flow control can always be put on the pump outlet to regulate flow.  The CS50 is only rated at 300gph flow rate, so I'd go with the CS90.  For additional info on subject, read here and linked files above.  http://www.wetwebmedia.com/plumbingmarart.htm>  
Thanks in advance.
<You're welcome.  James (Salty Dog)>
Wayne

Overflow Design/Bulkhead Size    10/3/06
Hello.
<<Howdy>>
I have a 135 gallon (6-foot) glass aquarium that is not drilled that I would like to set up as a reef.
<<Ok>>
After doing some reading on your site I'm leaning toward having the tank drilled and building some sort of gravity fed overflow, since siphon "CPR style" overflows seem to eventually fail.
<<Indeed...though I must admit I ran/used siphon overflows for more than a decade with but a few "failures" in that time... and nothing catastrophic as I always allowed for transient water volume in both sump and tank.  There are measures to take to increase reliability...and if using siphon overflows it is always a good idea to use "two".  But if you can drill this tank then I do suggest that is the way to go>>
I like the idea of drilling the holes on the back wall near the top of the tank (2-3" from the top would be ok??) in case a bulkhead leaks not all 135 gallons end up on the floor.
<<Mmm, yes...is my preference over drilling the bottom as well.  As for the holes, the edge of the drilled hole should be located at least the diameter of the hole away from any edge (top or side).  For example...a 1 1/2" bulkhead requires a 2 3/8" hole, thus, the hole should be located so it edges are no closed than 2 3/8" to any tank edge.  This is a bit conservative for some folks, but is a good rule of thumb for maintaining/maximizing strength/integrity of the glass panels>>
I was planning on 2 X 1 1/2" (inside diameter) bulkheads, would this be sufficient for approximately 1,000gph flow from the sump pump?
<<Should be, yes...and why not drill an "extra" bulkhead while you're at it?  This can be capped-off for now but will be available should you decide to add a closed-loop, etc.>>
Is it necessary to attach the internal overflow boxes around the bulkheads or could I just use some sort of basket shaped screen to keep critters from going through the hole?  The screen idea just seems much easier.
<<Indeed it is.  I have my tank drilled through the end walls (is an in-wall installation viewable from front and back).  I used "slip" bulkheads and modified 1 1/2" ABS 90-degree ells (notched edge of top opening) fitted with a short length of PVC pipe and inserted in to the bulkheads to create "mini" overflows.  Another method would be to simply insert bulkhead screens and design the drain plumbing coming from the bulkhead to the sump with a small "hump" just off the bulkhead to control/raise the water height in the tank above that of the bulkhead.  (Have I lost ya yet?)>>
If I did decide to build an overflow box do I have to use glass since nothing seems to permanently bind glass and acrylic?
<<Silicone will usually bind acrylic sufficiently for in-tank overflows>>
Is there anything else I could build it out of that would bind to the glass aquarium that is easy to cut and work with?
<<Give the acrylic/silicone a try...many overflows in manufactured tanks these days are plastic>>
Ok, one last question.  All the overflow boxes I have seen in stores always go from the top of the tank to the very bottom.
<<Generally because these tanks are bottom-drilled>>
I'm assuming this is because they are made for tanks that are drilled at the bottom.
<<Ah, yes!>>
Since I want to drill my tank near the top, can I build a much shorter overflow box, say 5-6 inches tall?
<<Indeed you can, though without support from resting on the bottom of the tank, glass might be a better choice over acrylic for the better "bond" with the silicone>>
What would you recommend as the minimum dimensions of each overflow box to accommodate a 1 1/2" (inside diameter) bulkhead?
<<Hmm, I'd try 5" high x 4" deep x the entire length of the back wall...but do a Google search on our site/the NET re "horizontal overflow" to get other perspectives on this>>
Thank you for all your help,
Jon
<<Happy to assist.  Regards, EricR>>

Re: Overflow Design/Bulkhead Size – 10/03/06
Eric,
<<Jon>>
Hey, thanks for all your help.
<<My pleasure>>
I really like your "mini" overflow idea.
<<Works for me <grin> >>
Is it very loud?
<<Nope>>
I read that many people install the "Durso" standpipes to quiet the water.
<<Tis is true but there are others ways to mitigate noise...reduce flow or increase the number of throughputs for same...aspirate the drain lines...>>
In your "mini" overflow design, I don't think that is possible, is it?
<<Would/is not possible, no>>
Is that a problem?
<<Not in my experience/with my configuration>>
Would two 1 ½-inch diameter elbows acting as the mini overflows be sufficient for a 135 gallon (1000 gph flow)?
<<Can’t say for sure without giving it a try but yes, likely so if you can aspirate the lines well enough to prevent surging/sucking.  But honestly, you don’t need to push this much water through your sump (you will have other means of providing water movement in the tank, yes?).  You can go ahead and use a pump rated at this capacity, but do install a gate-valve on the output side of the pump to allow you to reduce flow if necessary to quiet the overflows/the sound of the water rushing in to the sump>>
Are they screened off in any way of just have notches cut into them?
<<Just notches...and positioned high enough under the lip of the tank (acrylic) to prevent fish/astrea snails from entering.  If this is a concern, you can try rolling a bit of plastic “gutter guard” and inserting this in the ell (will need to be checked/cleaned periodically of any accumulation to prevent loss of flow)>>
Are they glued in or just pushed on?
<<A slip/friction fit>>
Would a thread X thread bulkhead work in this case too?
<<If you have enough clearance above the bulkhead to “spin” the elbow, yes>>
I'd want to be able to remove the elbow in case it needed cleaning or to be replaced, and would rather have it screw on rather than just push in, for safety's sake.
<<The slip fit has not been an problem in my experience, just be sure not to wedge it in so tight you can’t get it back out>>
The bulkhead screen idea seems good too.  Let me make sure I understand it though.
<<Alrighty>>
Inside the aquarium would only be the screen, about 3 inches underwater.
<<Correct>>
On the outside you would simply raise the pipe coming from the bulkhead a few inches up to the point where you want the level in the tank to be, by using a few elbows, right?
<<In theory, yes.  I have not tried this myself>>
Would it be a big deal that you wouldn't be skimming any water off the surface, rather just below?
<<This method doesn’t allow for removal of surface film>>
Ok, I'll leave you alone now.
<<Not a problem my friend>>
Thanks again,
Jon
<<A pleasure to share.  Eric Russell>>

Re2: Overflow Design/Bulkhead Size – 10/03/06
Eric,
<<Hiya Jon!>>
Hey, just wanted to say thanks again for all your help.
<<Truly my pleasure>>
I think you just solved my problem.
Jon
<<Ahh...is redeeming to hear (read).  Good luck with your venture my friend, EricR>>

Drain Flow Rate 9/27/06
Howdy guys and gals! Thanks very much for all the help so far!
<Hello Garth>   
My new tank has a corner built in overflow box with a 50mm (2") drain hole drilled in the bottom. with two 32mm (1 1/2") pump pressure returns drilled holes.
The drain return (to the sump) has a bulkhead fitting and due to that it ends up with 40mm (1 1/2") ID PVC pipe and a Durso submerged inlet (all 40mm - 1 1/2")
The pump pressure returns are also bulkhead fittings and end up as a 20mm (3/4") ID after the bulkhead fittings. But with the use of an adaptor I end up with 1" ID for the two pump pressure returns.
I plan on running two Oceanrunner OR2500 rated at 2500l/h each (625gph).
<The OR2500 is rated at 650gph.>
There will be approximately 4ft head  on these two pumps. So I will have a total of 5000l/h (1250 gph).
<With a four foot head on each pump, you will not have 1250gph, but somewhere around 700-750 gph which is well within the drain's capability.>
I would just like to know if my overflow will handle this flow rate.
Thanks for your kind words of wisdom.
<James (Salty Dog)>
All the best and take care.
Garth

Re:  Overflow And Pump Size 9/27/06
Hello again James,
Thank you for the quick response.
<You're welcome.>
In regards to connecting the sterilizer and chiller on the same pump, I had posed this question earlier on WWM. The chiller I have has a flow rate of 250-350 gph and the sterilizer a 100-200gph flow rate. EricR (who responded quickly as well) said that I should use separate pumps for each since trying to adjust proper flow would be difficult. Do you still think I should connect them all together, if not, do you still recommend a return pump of 500gph.
<You gave no flow rates on the equipment in your query to me, so I assumed they were sized for somewhere in the 300-350gph range.>
(I am adding EricR's response so you can see it in total.)
<Should have replied with Eric's suggestions, since he answered your original query and was aware of the equipment being used.  Much better for the same person to do the follow-up.>
I value everyone's opinion at WWM so any suggestion on which method to use will be greatly appreciated. I want to try and avoid  the whole "trial and error" process as much as possible.
<Now knowing the equipment you have, I would go with Eric's suggestion on the UV, and, if it were me, I'd go with a pump in the 400gph range and pump water from the sump, into the chiller, and back to the tank.  With the head pressure loss, you will be around 275-325 gph on the return, well within range of the chiller recommendation.  Additional flow rates can be increased in the tank by use of a powerhead.  This will give you flow in the tank from more than one direction.  Based on Eric and myself's suggestions, you will have to decide which method will work best in your situation.>
Once again thank you in advance.
<James (Salty Dog)>
Wayne

Overflow And Pump Size 9/26/06
Hello,
<Hello Wayne>
I am planning on upgrading my 15 gallon tank to a 35g with a 20g sump. My  tank is not drilled so I'll have to use an overflow to bring water to the sump. What type of overflow do you recommend (gph flow) for this size of tank and what gph pump do you suggest. I am thinking about using a SCWD wavemaker connected from the return pump.
I will be connecting a 9w sterilizer and a 1/10 chiller into the sump as well. Each  will have its own pump because of the differing water flow. The chiller and sterilizer will be pumped from the pumps in the sump back into the sump ( if that makes any sense). Only the return pump will be returning water back to the tank. Is this method of circulation o.k. or should I try it another way. I will have a skimmer, but due to the limited space in the sump it will have to be hung on the back of the tank.
Keep up the good work.
<Wayne, not a very good way to do is.  First off, the chiller will be turning on/off constantly as it will be looking at water already cooled for the most
part.  Same goes for the UV, you want it to look at as much tank water as possible.  I'd select at least a 500gph pump and connect everything in-line.  Pump through the chiller, then the UV, then back to tank.  Multiple pumps in a small system will use more energy and create more heat, and the chiller will run more
often, adding to the bill.  Overflows should be selected so that it's total flow rate is close to the pumps capability.  Oversized overflows create problems in this
regard, often leading to constantly removing air trapped in the "U" tube due to the slower flow rate through the tube.  I'd probably go with the CPR CS-90 overflow,
which will give you a maximum of 600gph flow rate.  This still puts you in between a rock and a hard spot.  The CPR CS-50 is a little shy on flow rate for your tank (300 gph), and the CS-90 is a little high at 600gph.   Your other option is to have the tank drilled, which would be the way I'd go.  It would still be cheaper than buying the overflow and eliminate the hassles of such, and less clutter in/on the tank. The 20 gallon sump would still be fine in this system.>
Thanks in advance.
<You're welcome.  James (Salty Dog)>
Wayne

120 gallon tank drilling pipe setup   9/16/06
I currently have a 75 gallon reef aquarium.  I bought a 120 gallon 6 foot long X 18 d X 21 tall aquarium that I want to have drilled for sump X 2 and refugium X 1.  If you think this is possible.
<Mmm... better to go with two good-sized overflows and use "Tees" and valves for water distribution below>
  I was going to make a total of six holes.  Two holes would be for outtake and return from under the tank wet/dry filter (it only has one intake hose), two holes for outtake and return for under the tank sump holding rock, sand, and mangroves (any other suggestions for what should be in this, such as mud, etc?)
<... posted on WWM. Read here: http://www.wetwebmedia.com/marsetupindex2.htm>
and two holes for outtake and return for above tank refugium containing rock, copepods, amphipods, Chaetomorpha, etc.  Where should I have these holes drilled and how would you hook up the system (which hole goes to and returns each system.
<Also posted>
  I saw you mention something about cages instead of an internal overflow, where can I get cages?
<Such thread on intake screens are available from online and not outfits like MarineDepot.com and All Seas if you're a dealer>
  Do you have pictures of a tank with cages instead of an internal overflow?  I want to avoid using power heads as well, Will the two returns
from the sump and filter be enough circulation?  Any suggestions you can give me that might make this better would be appreciated.
  Thanks Stephanie
<Keep reading my young friend... you're not quite "there." Bob Fenner>

Re: 120 gallon tank drilling pipe setup   9/17/06
Can you send me the passage on the slender horizontal overflow, does anyone make these for purchase?
   <... what? Please... keep reading. BobF>

Overflow box problems  - 09/03/06
Help
I have a 75 gallon vertical tank, octagon shaped.  I have a wet dry filtration system with a typical overflow box.  Every time I stick my hand into the tank to try and clean or feed my animals the overflow box stops working.
<Too touchy for my comfort...>
I know my hand and arm displace water but it is very frustrating to go through to process of restarting the wet dry circulation every time I put my arm in the tank.
Any recommendations?
Frustrated.
<Yes... I'd add another overflow... Please read here: http://www.wetwebmedia.com/overfloboxfaqs.htm
and the linked files above. Bob Fenner>

SW plumbing, overflows mostly  - 09/01/06
I am in the process of setting up a new aquarium and wanted to run the set up by the great team at WWM to see if there are any clear issues.
< 20+ heads are better than one! >
My new tank should be 170 gallons measuring 60"x25"x25". It will have a 40" horizontal weir overflow with 4 1" bulkheads. There will be 2 1" bulkheads for the return. I am looking to set up a small sump tank under the cabinet to take in all the overflows and run the skimmer. The water will then flow down to my basement using a 2" PVC
< You may want to consider multiple 2" lines. > <<And this size through-puts/bulkheads... the one-inchers won't do here. RMF>>
to my main sump which will be larger and contain a refugium. I will then use an Iwaki pump to return the water back up.
< A MD-100RLT, I presume! Great pumps. >
I wanted to keep the skimmer on the first floor because it's more convenient to clean but keep the rest in the basement because of easy access to water.
< Sounds great! The only concern I would have is the ability for the single 2" line to handle the flow from four 1" bulkheads. Simply doubling up should suffice. Good luck! RichardB > <<Mmm, what's that formula for the surface area of a circle? pi R squared.... do the math. Surprised? RMF>>

A Plethora of Plumbing Questions - 08/31/06
Hello,
<<Howdy>>
I have a few questions regarding plumbing my 120 tank to my sump.
<<Alrighty>>
I am setting this up as a FOWLR now, but planning for the flow for a full reef later.
<<Mmm, no reason your FOWLR shouldn't have this benefit as well>>
I have been reading WWM daily to get a good idea of how to plan things, I just wanted to run this info past you to see if all is good.
<<Ok...let's see what you've got>>
I have a 120(48x24x24)gal tank, it will be built into the wall with a utility room in the rear, so space is not a big issue.
<<Cool!>>
I am going to have it drilled locally at a glass shop.  I am going to use two 1-1/4" bulkheads for drill-bit size reasons.  I have 2 bulkheads to be installed that are 1-1/4"ID.  These will both feed the sump.  I plan on having them drilled aprox 5" from center to the top of the tank (in the corners), and in the tank, use two 1-1/4" 90's with a threaded strainer to skim the top.
<<Ah, yes...this is very similar to my drain/overflow configuration>>
After coming out of the back of the tank, I will use a reducer to go to 1-1/2" pipe.  I know that it will only flow the equivalent of the 1-1/4" flow bulkhead, but the 1-1/2" pipe is more readily available
<<Indeed>>
-What is the flow of each 1-1/4"?
<<There are many things that can "revise" what is essentially a laboratory environment/best possible scenario flow calculation...  The flow calculator on Reef Central says you can flow 920 gph through a 1.25" bulkhead drain...experience has taught me that reality is about HALF the calculated rate.  You can squeeze out more, but for reasons of complexity/noise/hassle you will be better off adding more throughputs if you need/desire more flow than this>>
From the reducer it will go into a T-wye for better flow movement, and will run above the tank a few inches to be topped off with a cap on each Over-Flow that will be drilled at the top to allow for air to vent.  
<<You'll find inserting a length of tubing through the vent-hole in to the pipe a short ways will be more efficient than the vent-hole alone>>
Then running down via a 1-1/2" pipe it will go into the sump via a 1 1/4" reducer.
<<...?>>
My sump lid is already drilled for the 1 1/4".
<<Ah!...I see now>>
Will this second size change hurt flow at all?
<<Will be a "slight" hindrance/increase in friction as the water navigates the "bump in the road">>
I plan on having 2 unions installed and 2 gate valves.
<<Unions are fine, but I wouldn't put valves on the drain lines...too much flow restriction and chance for blockage>>
I will also allow for an additional T somewhere in there for convenient water changes and maybe feeding a fuge later.
<<Good planning>>
OK, with this said, here are a few of my questions:
-What do you think my total flow will be with the 2 1-1/4" bulkheads?
<<As outlined previously...about 900 gph or so, before things start to become problematic>>
-Do I need to go to 1-1/2" bulkheads?
<<If you want more flow than this, yes.  But I see no reason to push more water than this through your sump.  You may want to consider additional throughputs for a closed-loop for more water movement within the display tank>>
-Is converting to the 1-1/2" in the middle causing any flow issues?
<<No>>
-Where in here should I put my UV?
<<Mmm...should not be plumbed in-line with the drain>>
Should it just get its feed from the sump and use
a pump or add another T + reducer to use gravity to feed the flow with a gate valve?
<<Best configured/flow regulated through a dedicated pump>>
-Will the UV just return to the sump?
<<Up to you...can be plumbed to simply recirculate in the sump if you wish...or can be plumbed from the sump to the display>>
It's a 15-watt (I know it's a little small but I'm using it for now) will it do any good?
<<Again, up to you...its efficiency will depend greatly on how diligent you are about keeping the lamp sleeve clean...but yes, will likely provide "some" benefit, though these units are more trouble than they're worth in many cases...in my humble opinion>>
-I have an in sump skimmer, should be OK..??
<<No idea/not enough info, but if it came with the sump I have doubts as to its quality/efficiency>>
-Will running 45's instead of sweeping 90's matter for me?
<<If true "sweeps"...no>>
-My sump is 30x12x14T, is this big enough for this flow?
<<Many variables to be considered here (plumbing configuration, dynamic water levels, transient water volume, etc., and not the least of which, your (your spouse's) tolerance for noise), but generally speaking this should handle 900 gph just fine>>
I will start with the bio balls and evaluate later to remove.
-For now I would like to go with an in sump pump, maybe a MAG, can I use just one pump and feed it up to a "T" with two over tank feeds?
<<You can>>  
-Or should I use two pumps???$$$$
<<A single pump suitably sized will serve fine.  My advice would be to "oversize" the pump slightly and install a gate-valve on the output side to temper flow as needed.  You'll appreciate the extra power/push once the plumbing lines begin to restrict from the inevitable build-up of bio-film>>
-I would like to just use one, can I get enough flow to turn the water over 10-15 times an hour?
<<Not with two 1.25" bulkhead drains...nor may you want to push this much water through the sump...but at any rate, this much flow will require more or bigger throughputs>>
-If I use just one, what size would you recommend to return lines before and after the "T"?
<<Best to follow the manufacturer's recommendations>>
Or if, I use two with no "T" what size line?  Can I start with one pump and a "T" setup to save $$ and change later to two later?
<<Sure...changing to two pumps is not necessary, though having the "built-in" redundancy is not a bad thing in case of a pump failure>>
-What size pump, in flow - do you recommend for this setup?
<<A Mag-12, with previously mentioned gate-valve installed>>
Which in-sump pump is best for low heat?
<<The MagDrive pump work well for me>>
-Are gate- or ball-valves better for me?
<<Gate-valves...much easier to make fine adjustments>>
-Would this whole thing work better with an external pump?
<<Either can do the job...but a submersible pump is usually easier to employ>>
Whew!!!!  Thanks so much for taking the time to help with my, I mean our, Obsession!!!
<<Indeed my friend...I'm happy to assist>>
Hopefully this all makes sense to you.
<<Yes>>
And sorry for all the questions!
<<No worries>>
BTW, this is tank #4 in my house, I'm finally growing up at 36, and getting away from the hang on filters.
Randy
<<Good luck with your project, EricR...49 as of yesterday and still not quite grown up>>

Tank perimeter trim and back wall over flow vents   8/30/06
Hey crew!
<Jean-T>
I made a sump out of an old 55 gal tank. I added silicone over the existing silicone
<Not a good practice... doesn't adhere well. Should be cut out, replaced...>
just to be safe. (I know this is somewhat useless since its the film between the glass that does the job..
<Oh! Yes>
but I feel better still)
I noticed that the plastic perimeter trim on the top and bottom of the tank was cracked in all corners.
<Mmm, this is more for assembly, looks than structural...>
I am having a hard time finding replacements at local pet shops and have no  credit cards to order them via internet.
<Make a deal with someone who does... send them a check in advance...>
Do I really need this trim ?
<Mmm, very likely not>
I have 4 baffles in the sump so this may compensate as reinforcement??
<To some extent yes... I wouldn't worry re... you probably won't have this filled very high...>
   Also I have 4 drains across the top of my back wall (1 inch bulk head)  and my pump will be pushing 1200 gph.
Do I need to pipe  vents into the overflows so they can draw air?
<Mmm, likely a very good idea to have "tees" at the down junctions... may well have to aspirate these to cut the "gurgling" noise... See WWM...>
  I once herd that if no vent is present it can greatly lessen flow? is his true?
<Mmm, in some cases these small diameter lines can/do operate as siphons... but this is not a good idea all the way around... if the size, number of drains is insufficient and one or more should become occluded...>
Do you think my drains will handle 1200 gph?
<No... all this is gone over and over...>
my return to the tank is via  4   3/4 inch  returns ? does this sound right for 1200 gph in a 90 gal tank?
<Depends on the pumping mechanism, but no... not real 1,200 gallons per hour>
tanks so ever very much for your precious time! thanks!!!!!!!!!!
  Tristan!!!
<Please read here: http://wetwebmedia.com/marsetupindex2.htm
Scroll down to the areas on plumbing, overflows, bulkheads, noise... and read... Better to re-drill, fit large-enough through-puts now. Bob Fenner>

Using Old Rock/Drilling Bulkheads - 08/27/06
Hey guys,
<<Hello (but don't forget the very capable ladies here as well)>>
Thanks again for your time and dedication to our hobby!
<<Is an honor/pleasure to help>>  
I have 2 issues I need help with:
<<Alrighty>>
First, I have read thru the LR section in depth and could not find an exact match to my problem.  I recently purchased a used, and neglected 120 gallon that housed a single clown grouper with several large pieces of rock (it was a FO with rock??).
<<Indeed...that would be a FOWLR (Fish Only With Live Rock)>>
I have kept the rock wet for a few days and can see a few small life forms on it (actual moving little white/clear bug things).
<<Amphipods...probably>>
The rock looks terrible as the tank was neglected and the rock is all dark brown and black.  I will be setting this tank up as a FOWLR and I am thinking that I would like to start over with the rock.  Letting it dry and cleaning it somehow and then letting it cure in the tank for a month or two before adding new fish (pending testing results).
<<Mmm...letting the rock "dry out" will negate its benefits...why not simply keep the rock as it is?  If the color is an issue, it will likely change with improved water quality/lighting>>
Can I get the rock to look better?
<<Depends on what you consider is "better">>
Is it worth losing whatever life it has on it?
<<Not in my opinion>>
It was not really a traditional live rock,
<<...???>>
it has life but it looks very bad.  They are great sized pieces.  The substrate is crushed coral, I would like to reuse it.  It also has black and brown staining on it.
<<This is most likely forms of algae, and will "change" with changes to the environment, as stated>>
Can this also be cleaned?  If so how?
<<Swirling/rinsing with clean saltwater will do the least damage, though you will still loose some biota>>
I don't mind starting over on the rock but will my cleaning methods effect any future fish or possible changes to inverts/coral down the road if I go that direction?
<<Indeed it will...you could give the rock a rinse and a "light" brushing with a soft-bristle brush, or replace it (entirely or in portions) with fresh live rock>>
Second, the tank is a traditional (non RR) tank.  It came with a sump/wet-dry and a HOT overflow.  I am weary of the overflow as I hear that they will eventually fail.
<<Is a good chance, yes...but this risk can be lessened a great deal by employing a redundant system (two siphon overflow boxes) with the first>>
I have once again read on WWM about tank drilling and am thoroughly confused by all the different opinions and issues.
<<Let's see if I can help un-confuse you>>
I would like to drill the rear for 2 sump supplies and 2 sump returns.  Where exactly (how far down and over/apart) do you recommend?
<<Well, if you've established the back glass in non-tempered, I recommend you place the throughputs the width of the hole-to-be-drilled from the edges of the tank, and no closer re to any other throughputs...clear as mud?  For example...a heavy duty 1.5" bulkhead requires a 2.6" hole...the edge of the hole should be no closer than 2.6" from any edge of the tank, or from any edge of another bulkhead hole.  Adjustment of water height in the tank can be accomplished with elbows to raise the level of the pipe outside the tank, or used as adjustable "overflows" within the tank>>
Also what size is best for this size tank if I use a strainer for the supplies down and a directional elbow for the return up?
<<Two 1.5" bulkheads for the drains, and one or two .75" or 1" bulkheads for the returns...or you can simply plumb the returns over the back/ends of the tank>>
Should both the supply and the return have a T installed before the sump?
<<For what purpose?...in what configuration?>>
Also, are there and tips for drilling?
<<Indeed, yes...have a read here:  http://www.wetwebmedia.com/pbholesfaqs.htm >>
I have seen a tank drilled before and they used cooking oil for the lubricant while cutting?  Is this OK?
<<I've always just used water for lubricating the drill bit...works well and is easy to clean up>>
I plan on ordering the needed bits online, any recommended sources?
<<Several choices about...I bought my last bit here: http://www.diamond-drill-bit-and-tool.com/Diamond-Drill/MAIN.htm >>
Any tips?  
<<Heat is your enemy...follow the recommended rotation speed for the size core drill bit used.  The manufacturer states these bits can be used "dry", but use of a lubricant (water) will keep heat down, greatly extend the life of the bit, and speed the drilling process...I use simple 'Play-Dough' to create a "damn" around the area to be drilled and fill/refill with water as needed while drilling.  Also, when possible, use of a drill-press or drill-jig to keep the bit vertical to the glass surface will lessen the chance of damage/fracture of the panel>>
Thanks once again for your help and contribution to our obsession!!!
Randy
<<Quite welcome.  Regards, EricR>>

Refugium Size/Overflow Surge/Skimmer Adjustment - 08/25/06
Hi Everyone,
<<Hello Diana!>>
I just installed a Refugium (it is 36"x18"x13" with the refugium being 15"x13" does that seem big enough for my tank?) on my 150 Gallon reef tank.
<<Whether this is "big enough" is a question that can't really be answered...bigger the better as you are probably aware.  But the fact it is there "will" provide benefit to your system>>
I have two pumps in my return (one for returning water straight back to the tank the other goes thru the chiller and UV light).
Now here is my problem.......When I have both pumps running the overflow on one side of the tank is putting out air thru the hose back into the skimmer area.
<<Is having problems handling the volume...efficiently>>
It seems like the overflow pipe is filling up to fast with water and the air hole in the overflow pipe can't keep up so it creates suction.  Does this make sense?
<<Sorta <grin>.  What's happening is the volume of water traveling through the pipe with both pumps running is trapping/preventing the air in the pipe from escaping efficiently.  This are is then pushed to the sump (the bubbles you see being created there) and/or building to the point that it surges back up the overflow pipe (intermittent rushing/flushing sounds)>>
My question is how it comes that it only does it on one side and when both pumps are running (I guess I answered that one already since it is putting more water into the tank with both pumps on).
<<Indeed>>
Now my main question would be how I can fix this problem?  Any help would be appreciated as I would like to get my water flow going again and make my fishies and corals happy.
<<The easiest solution would be to install gate-valves on the "output" side of the pumps and temper the flow down to what the overflow can quietly and efficiently handle.  Another approach is to "aspirate" the return line by inserting a length of small diameter tubing (exact diameter and length of insertion will require experimentation do determine optimum performance) to help with the escape of entrained air from the line.  This method will usually yield some improvement to water flow but is no panacea on its own and will probably work best if employed with the addition of the gate-valves as mentioned previously>>
One other quick question, if you don't mind.
<<Not at all...>>
I just hooked up an ASM G2 Skimmer in my refugium and I was wondering if there is any hints on how to get it working just right (as of now I'm only getting greenish water)?
<<Simple adjustment of the riser-pipe will change the concentration of the skimmate.  If the skimmate is too thin for your liking, adjusting the riser-pipe "down" will lower the water level in the skimmer body yielding a thicker skimmate... you will likely have to "play" with the adjustment a bit to find the desired height/skimmate production>>
Thank You,
Diana
<<Quite welcome.  EricR>>

Equipment...Tank Modification   8/19/06
Hey guys/gals...
<Hello Dave>
This may be my fastest question yet...
<And, my fastest answer.>
and I'm pretty sure you don't have anything posted on your resources.
I have a pretty standard 90 gallon that's been running for 4yrs.  I want to start getting into corals and am taking the necessary steps to accommodate them.  I bought a Tunze Wavebox thinking that the massive yet gentle flow back and forth would be great for the corals...
<Is>
however, my corner overflow in the tank was built a touch too high.  I have about 2cm of room between the water top and the lip of the top border around the tank.  Tunze recommends a MINIMUM of 5cm.  I don't want to drain the tank and have the overflow ripped out.  The plastic (or whatever it is) border on the top that includes the lip for which to place the glass covers (do u <you> know what I am talking about?)...
<Yes>
from what I've seen, most tanks have them.   Can this be easily knocked off the top or removed??
<If you are talking about the black/oak trim on the top of the tank,
<<Is not... is talking re the inside structure for the tank's overflow... if plastic of some sort this can be cut, though not easily... I would drain the tank to do this... many bits of plastic otherwise... RMF>>
 (glass tank I presume??) this small lip that supports the glass can be
removed to accommodate the space the wavemaker needs. Is this is what you have in mind?  Have you ever heard of anyone building more height onto their tank?
<No, not safely.>
I'd like another inch or inch and a half.  Note, the water level would never be higher than the original sturdy glass... the extra inch or so of glass would merely serve as to accommodate the little 5cm water movement from the wave.  Any suggestions, comments, advice??
<I'd contact Tunze with the above question, get some input from them.  http://www.tunze.com/117.html?C=US&L=1>
If not... would a Tunze Wavebox have any outstanding benefit in a fish only predator tank of 200 gallons?
<Yes, very beneficial.  Will help keep detritus/waste suspended for more efficient removal from the tank.  Also has a cleansing effect on the rocks, corals, etc.  James (Salty Dog)>
Dave

Overflow Noise/Glass Scratches - 08/15/06
Hi,
<<Hello!>>
I have a 54G RR Corner tank with a 1" drain and a 3/4" return.
<<Sadly undersized throughputs...even on this volume of water>>
I bought the whole reef set up used, but I can't imagine how the previous owner tolerated the noise!
<<Mmm, indeed...you can't really put much water through a 1" drain before it becomes problematic>>
I installed a 1.25" Durso standpipe (1" did not work, now I follow directions, doh!).  I have a 1/8" drilled hole in the top of the T of the Durso.  It was fascinating to watch the relationship between the air hole size, the drain line position relative to the sump water level, and the gurgling and flushing effect.
<<Ah yes, you are finding out just how "fiddly" it can be.  I would like to suggest you try enlarging the hole just enough to push some airline tubing through and down in to the standpipe.  This will help with aspirating/releasing air from the drain line and often eases the gurgling sounds.  It will take some experimentation to determine the best length/diameter tubing to insert>>
As I slowly increased the air hole from a pinhole up to 1/8", I observed the step by step decrease in flushing effect amplitude.  
<<Yes...allowing that air I mentioned to escape more readily>>
It started at about a 3-inch oscillation, at 1/8, it was gone completely.  Adjusting the drain pipe position also impacted the flushing effect and required small changes in the air hole.  
<<Pretty much all comes down to eliminating the obstructions (air bubbles) to the water flow>>   
OK, on to my questions:  I have extensive bubbling/gurgling noise in the sump from the drain.
<<From air that is "carried" down the line by the water>>
I have read on WWM two things to try: A "T" or "Y" fitting on the drain line, and aspirating the drain line from the top with air line tubing.
<<Yes indeedy...though I prefer a 45- or 90-degree ell fitting on the end of the drain line>>
I am confused about the specifics of both of these.  For the T or Y fitting, how is it positioned?
<<Is of little consequence...just position to direct flow in the direction you desire>>
I am guessing that it goes at the bottom of the drain line, with one leg submerged and one leg above the sump water level?
<<Mmm, okay...I think I'm with you now.  The purpose of the fitting on the end of the drain line is to "slow" the rush of water a bit.  So...experiment with the position to determine which gives you best results.  Either way you position it, I find that having the end of the drain line completely submerged usually works best.  And do be aware, it is usually not practical to expect a 1" drain to flow more than about 300/350 gph without much hassle and noise, as you seem to be experiencing>>
For the aspiration tubing, is the tube supposed to have its own hole separate from the existing air line in the Durso T cap?
<<Refer to my earlier comments re>>
Or does it simply go down the same hole?
<<Yup!>>
It also seems to me that the bubble/gurgle would be reduced if I had the water break on some live rock rubble or other irregular surface.
<<Can give it a try>>
I think I have seen reference to using filter pad material.
<<A detritus trap>>  
Next question: Even though I only have about a 2-inch drop from the overflow wall to the top of the water behind it, it still makes an annoying, trickle noise that induces the need to visit the bathroom at night (tank is in the bedroom).
<<Hee!>>
I am thinking of installing some kind of stepladder down to the surface.  Or perhaps a piece of filter pad would also suffice.  How have you seen this done?
<<Raise the height of the standpipe to raise the surface of the water in the overflow...it only needs to "fall" a fraction of an inch or so>>   
Last, the tank is used, and has a good number of extremely fine scratches that are visible depending on angle and lighting.  I have read that you generally shy away from glass polishing/buffing, but that usually seemed to be because the e-mailer was asking about significant/deep scratches.  What do you think about using a commercial buffer on an orbital drill pad, and follow with a thorough cleaning?
<<I think you'll do one of two things...nothing at all...or make it worse.  Scratches in glass "can" be repaired/removed, but unless you really know what you're doing/have done this before, I recommend you refer to a professional for advice/consultation.  You may find it is easier/cheaper to replace the tank...or learn to ignore/accept the scratches>>
Jack
<<Regards, EricR>>

Overflow box/es...?   7/31/06
I am in the final stages of setting up a 157 gal reef tank. Besides the tank volume it will also have a 40 gal sump. I bought a Iwaki pump rated at 1100 gph. My question is how large of a overflow box should I purchase (I know a drilled tank would be best but one buys what one gets a great buy on) Should I purchase one rated at 1100 gph or one larger and then adjust it to the flow I need.
Thanks
Robert
<I would purchase/use two such designated flow devices, if not re-consider having the tank drilled... Much to discuss... Please read here: http://wetwebmedia.com/overfloboxfaqs.htm
and the linked files above where you'll lead yourself, till you feel confident re what your choices are, your best direction here. Bob Fenner>

New Display-Questions on Bulkheads/Sumps/Filtration - 07/21/06
Dear WWM Crewmember,
<<EricR here...how can I be of service?>>
I have been a freshwater aquarist (125 gallon) for many years and am now taking the leap to marine.
<<The experience will serve you well...but still, much reading/research ahead of you>>
I have researched your excellent site and read through The Conscientious Marine Aquarist.
<<A good start, but don't limit your research to a single source.  Opinions/experience is varied and wide.  Gather your information from varied sources and use your own good judgment to make decisions re>>
I have learned tons but still have a few questions regarding my specific needs.
<<Alrighty>>
I am interested in purchasing a 175 gallon Oceanic bowfront w/ two MegaFlow overflows (rated at 650 gph each, for a total of 1,300 gph).
<<Mmm yes, generally undersized and overrated overflow systems.  For simplicity of plumbing/maintenance, and to ease noise/bubble issues, I would plan on/expect about half the rated flow>>
Although I intend for it to be a FOWLR set-up, I know one day after much experience I may want it to become a reef tank and want to plan accordingly for flow.
<<Yes, best/easiest to plan/plumb at this stage>>
Not to mention I'd also like the flow increased for the FOWLR set-up anyway.
<<Indeed...vigorous water flow benefits fish as well as coral>>
Therefore, when placing my tank order from my LFS I am going to have Oceanic drill larger bulkhead openings.
<<Ah!  You "have" been doing some research!  Excellent my friend>>
It comes standard w/ holes large enough for 1" outlet and 3/4" return inlet.
<<Yes...unfortunately>>
I'm hoping the MegaFlow overflow is large enough for holes sized to accommodate 2" bulkheads.  Do you know if this can fit in their MegaFlow overflow?
<<Mmm, don't know...perhaps you can order these "upsized" as well>>
What about increasing the 3/4" return inlet if it fits within the overflow - should I do this as well?
<<I would, yes (1").  Can always be "necked-down" at the tank if you need more "velocity">>
Any bulkhead size recommendations for this specific overflow would be appreciated.
<<As big as you can go with the current overflow box...or upscale the overflow box>>
On to sump/refugium questions...
<<Okay>>
I am planning on purchasing a 55 gallon capacity sump/refugium from S P Aquatics...
<<No chance of separate vessels for these?  Using a single vessel for both can be/is done by many, but generally one methodology (sump or refugium) or the other suffers, in my opinion.  But I find separating the two eases equipment placement, attenuating flow for each, maximizing space, etc....and greatly simplifies isolating one from the other when/if necessary for maintenance/repair>>
They have two designs (or will customize) and I have no idea which might be best for my set-up.  The "X1" models have the display drain area on one side, water moving through refugium in middle, then water moving to skimmer/return area on the other side. The "X2" models have a display drain/skimmer area on one side, another display drain/refugium area on the opposite side, with both sides flowing water to a middle return area.  Any ideas on which one might be best?
<<I think the "X2" is the better design...less chance for the skimmer to "rob" you of beneficial organisms from the refugium>>
I plan on using a EuroReef CS8-3 skimmer.
<<Ahh, wonderful...I love these skimmers...use a CS12-3 myself>>
Also, in addition to the skimmer, I'll use live rock in both the tank and refugium - should I employ wet/dry filtration in this sump as well?
<<I wouldn't, will consume a lot of space which will already be at a premium as you'll discover.  Obtain and use a fluidized-bed filter...great for FO/FOWLR systems...will ramp-up/adjust quickly with fluctuating bio-loads.  Will also be much easier to "disengage" than a wet-dry when the time comes>>
Your help is much appreciated - thank you.
Martin
<<Happy to assist.  EricR>>

Wet-dry, overflow, pump... how do it work altogether?    7/13/06
I currently own an Amiracle Wet Dry filter that sits by the side of my 75 gallon aquarium and takes up space.  I unplugged it about a year ago because every time I turned it on, I either had water that overflowed the sump or that overflowed the aquarium.  When I called the manufacturer, they advised that if I installed the right return pump, I should never have this problem, and they recommended that I purchase a particular pump.  However, the pump that they recommended had been discontinued.  What do you recommend?
Murray Meeker
<Mmm, reading here: http://www.wetwebmedia.com/overfloboxfaqs.htm
and the linked files above to gain a "good-enough" understanding of what you're up to here. There needs to be a balance twixt the total volume of water present and what is "in play" in terms of flow rate through the device/s used to get water from the main tank and back... Not a guessing or blind game of "who said what". Understand what you're doing, then act. Bob Fenner>

Closed-Loop Plumbed Through Overflow? - 07/13/06
Friends at WWM,
<<Greetings Scott>>
What kind of problems would you foresee running a closed-loop and a sump out of the same overflow box?
<<Hmm...would appreciate a bit more information to wholly understand what you are attempting. You'll need to plumb each to its own throughput/drain...you'll need to ensure the box can handle the volume of water/won't starve the pumps...and then there's the noise such flow/volume brings...>>
Thanks,
Scott
<<Regards, EricR>>

Optimistic Flow Rates - 07/11/06
First of all great website, I've learned tons and spent hours reading posts, thank you.
<<You're quite welcome...glad you find the site beneficial>>
I tried to find my question but had no luck.
<<Let's see if I can help>>>>
I have a 300 gal FOWLR with a 50 gal sump.  I am running two twin tube hang on the back overflows, both with twin 1" drains.  I read I should be gravity feeding 1200 GPH for each box totaling 2400 GPH to my sump.
<<Read?  Where?  No way on Earth you're gonna get 1200 gph to "gravity flow" through a 1" drain.  1200 gph may be the "rated" flow on the overflow boxes...but it's not going to happen with a single 1" drain>>
My return pump is the Mag 2400.  I want high flow as I have groupers and triggers in this tank.
<<Mmm, yes...most all fish species appreciate good water flow.  Though I'm skeptical when it comes to processing this much water through a sump.  But if the noise, bubbles, splash is not an issue with you...>>
I used 1" for everything.
<<Not big enough>>
Right off the pump I have a check-valve, spring type from Lowes and a ball-valve on top of that all in the return line.
<<The check-valve is not a good idea.  Aside from metal contamination from the spring and the huge lose of flow incurred when using these devices, the valve will inevitably fail at some point...usually when no one is around for a long period.  Much better to adjust your skimmer boxes, return lines, and the water level in the sump to handle all transient water when the power is off.  I'd also like to suggest you replace the ball-valve with a gate-valve...will give you much more "finesse" when flow adjustment is necessary>>
Then it goes up the back of the tank and tee's to the ends when I have a 90 up then a 90 over then a 90 down and a 45 into the tank.
<<Mmm...head pressure indeed.  Between the check-valve and the elbows I doubt your getting little more than half the rated flow of the pump>>
I hope you can picture this.
<<I can>>
The problem is even with all that head pressure from 10 90-degree fittings, the ball-valve and the 45-degree fittings, I can't run the pump at even 50% or the aquarium overflows.
<<Not surprising.  At the "most", I think you should expect 500-600 gph from the 1" drains...about half that if you want a bit of a "safety margin" or to keep things quiet>>
I have to turn the ball-valve closed by almost half way for the tank to not overflow.
<<Indeed>>
Will changing the return plumbing to 2" help fix my problem?
<<Ahh yes!  Will improve things by a huge margin>>
Very confused, and lots of different formulas and theories.
<<Agreed...and most seem a bit "optimistic" to me where flow rates are concerned>>
Please Help.
Thank you,
David
<<I hope I have.  Regards, EricR>>

Optimistic Flow Rates II - 07/11/06
Ok, I was told by US Plastic's that a 1" drain will flow approximately 600GPH.
<<Yes...hear this all the time.  But I can tell you a more practical expectation is about half that.  A 1" drain may indeed be "physically capable" of allowing a gravity flow of 600 gph...getting it to work so in an aquarium application is another matter>>
My overflow boxes have dual 1" drains.  That's where I figured 1200GPH per overflow box.
<<Oh, okay...did not get that from the first email>>
Four 1" drains for a total of 2400 draining to the sump.
<<I see now.  But as you have discovered...not a practical flow rate>>
The bottom of the overflow box has a 1" union going through it.
<<Not a "union", is a "bulkhead"...two different fittings>>
So do I need to try and drill a bigger hole in the bottom of the overflow box to accommodate for a bigger bulkhead or can I just adapt a 2-inch pipe to the 1-inch bulkhead.
<<To increase the flow rate you will need to increase the size of the throughput (bulkhead fitting and drain pipe).  Just adding a larger pipe to the 1" bulkhead won't help, it still leaves you with the smaller restriction at the bulkhead>>
I also have the 1" U tubes.  Do those also need to be bigger?
<<Likely bigger AND more of them.  Actually, you might try this first.  With all the head pressure on your pump, the four 1" drains may well handle the flow and the real problem is your siphon tubes are not keeping up>>
And worst case if I can't drill the bottom of the acrylic box to adapt for a