Acrylic vs. glass tanks   12/19/06
Dear Mr. Fenner,
<Well, you've got Jorie here instead of Bob- I'll try my best to help you out!>
I read your article, "Tanks, Stands & Covers for Marine Aquarium Systems"
<Great article written by Bob...>
I am about to purchase a relatively large (280 gal) aquarium which will serve as a room divider in our new home.  I have been struggling greatly with my attempt to decide between acrylic or glass (Starphire).  I have read so many differing opinions on the two choices. Most of the criticism surrounding acrylic is related to its ease of scratching.  Others have stated it becomes opaque.  Can you speak further to this matter?  I simply do not wish to buy a tank of this size and for a significant amount of money and regret my purchase.  I wish for a tank to last many years.
<I applaud you for putting so much thought into this decision - always best to research before buying, doing; the same holds true for when you're ready to stock your new tank as well!  With regards to glass vs. acrylic tanks, well, like many things, there are pros and cons to both.  The concerns you mention about acrylic are valid - indeed, it is quite easy to scratch an acrylic tank, and I have seen some become cloudy with age. Our personal experience reveals that the former is more likely to happen than the latter - indeed, all of our acrylic tanks are scratched in places. However, there are algae-scrubbing pads and such made especially for acrylic tanks.  The benefits of acrylic, in contrast to glass, are its strength and flexibility.  Also, it's much lighter than glass (weight-wise).  Ultimately, it becomes a matter of personal preference; these concerns generally balance each other out.
The one personal suggestion I would give you with regard to investing in a new tank is to not get a bowfront (or any non-rectangular shaped tank, for that matter).  Our saltwater tank is a 46 gal. acrylic bowfront, I can honestly tell you that the viewing is greatly distorted by the curve.  All other things being equal, I (we - it's really my boyfriend's tank!) wouldn't purchase that same tank again.  I also have a 44 gal. pentagon-shaped glass freshwater tank - that one creates its own problems (e.g., proper lighting and being able to reach the bottom, both due to the height of the tank). This was my first tank purchase, and I thought it was great, since it was "unique".  Of all my tanks, I'm happiest with the "standard" 29 gal. rectangular tank which houses my brackish fish.>  
The broad spectrum of information is very hard for me to digest and make my decision.  Can you help me any more than your article already did as far as your preference for acrylic?
<That would be Bob's preference, it seems!  I think the glass vs. acrylic decision results in very personal opinions.  I do see some merit in going with acrylic for the larger-sized tanks (again, for strength reasons, if nothing else), but I won't lie - you will ultimately seem some scratches.  Not the end of the world, but they will inevitably happen.> <<I do prefer acrylic for most applications... but only have two glass tanks presently... with some scratches... RMF>>
Thanks, Keith
xxx.xxx.xxxx
<Hope I've helped a bit, Keith.  No concrete answer here, all you can do is lots of homework, then weigh your options.  Either choice will be just fine, in all likelihood! Best regards, Jorie>

Tanks and earthquakes
Hello everybody,
<Howdy>
I'm sitting in my leaving room 3 meters away from my 60 gallon glass tank and about 20 kilometers away from the north Anatolian earthquake fault line in Istanbul, Turkey. The fault line is told to be very similar to the Californian quake fault line. About 4 years ago a big earthquake hit the region and we wait for the next big one to happen, closer to the city of Istanbul this time, with a 60% chance if I recall correctly within the next 30 years, hitting 6.5 -7.4 on the scale. It may just happen next minute. Can you tell me anything about how to secure an aquarium against earthquakes? So far I have an anti-slip sheet between the tank bottom and the tank stand, and that's it. I want to upgrade to a 100 gallon 80" tank but the idea of 900 pounds of water and rock pouring on  me as the earth tries to shake us off it's back scares me a little. So, any ideas or experiences will be highly appreciated.
Thanks,
Husnu
<I share your concern. Please take a leisurely read through the marine sections of our site (WetWebMedia.com) under "Set-Up", particularly "Tanks" "Stands"... and the accompanying FAQs files. We like acrylic tanks (over glass) where the ground shakes but good... and to build stands that are braced in three dimensions... wedging them into corners, between other heavy furniture... even attaching them to walls. Many other ideas apply. Bob Fenner>

Glass or acrylic for commercial lobster store
Good evening crew.
<good evening>
We `are adding 7 tanks to our saltwater system. 4m long, 1m wide and 600 to 900 high. We will have lobster and shellfish in plastic cases. Water temp, 13oCelsius (Fahrenheit?..) Air conditioning in the room at 21o Celsius. We have been given mixed advice about using glass or acrylic. Is glass strong enough, will it crack, will it have condensation running down it. Your thoughts please..
Regards, Cameron
<lets play it safe here and consult the specs sheet for a glass and acrylic manufacturer. Glass can easily do the job (has done so for many years in public aquaria easily up to 1000 gallons). But it is a poor insulator and sweats terribly when holding chilled water. Either way, seek tolerances of "deflection" (ability of pane to bow without breaking) to confirm that your expected capture of the panes is consistent with mfg recommendations/expectations. Anthony>

Concerns about tank thickness
Hello Wet Web Crew,
<Hi there>
Wanted to first mention how great your site is, I've learned so much from browsing the FAQs.
<Glad you have benefited>
Quick question regarding minimal thickness on an aquarium tank. I've recently had built a 48x24x24 clear for life aquarium - unfortunately this was before I found the info on your site. They used 3/8" thickness, as opposed to 1/2" recommended by your site. Should I be concerned?
<Mmm, minimally. There may be a bit of bowing but the system won't fail>
I am somewhat paranoid that I'll come home to a swamp of 120 gallons in my living room floor slowly seeping down to my neighbors apartment. I hope that the only thing I should be concerned about is a little bowing. Also, anything I can do to prevent that (I was thinking of adding a strut in the back of the tank, but am fearful that this may make bowing more significant in the front!).
Thx, Tom
<This won't happen, unless there's a sizable earthquake... or a poor stand support. No worries. Bob Fenner>

Glass vs. Acrylic- The Tough Decision! 
Hello all out there, this question is to all of you, as I would appreciate as many opinions as possible. 
<Scott F. chiming in today> 
I am going to upgrade to a 180 gallon reef. I am going to be using the Aquamedic AquaSpacelight for lighting my LPS-dominant reef tank with 2-150w 10k MH's on the ends and 1-150w 20k MH in the center. I cannot decide whether to go with acrylic or glass. 
<Ahh...a common cause of consternation!> 
I would have 3 cut-outs on top where the light would be penetrating the most. I'm wondering if the existing acrylic top would interfere with the light getting into the tank, as I currently run my all-glass reef without any top. 
<Well, the acrylic will definitely reduce some of the light. On the other hand, with high intensity halide lighting, you're not loosing all that much. If it were me, and I were ordering a new tank (as I am about to, myself!), I'd opt to go with a "Euro Brace" configuration, which is essentially a completely open top, with just a perimeter of several inches around the sides. This allows maximum light penetration and circulation. It can be a bit pricey to do in acrylic, though, as I am finding out. Extra-thick acrylic is generally used in these types of situations, as the acrylic can bow if not braced, unless sufficiently thick acrylic is used. Glass tanks do have similar issues in terms of thickness, but they are generally much more commonly found in this configuration> 
Also are there any other factors that would make me lean either towards glass or acrylic besides scratching? (Is it really that bad?) 
<As someone who has scratched up his acrylic tank pretty badly, I think it is a big issue. You need to be aware of the scratch potential when scraping algae, or performing maintenance and aquascaping tasks in the system. The other consideration that you should think about is what I call "DIY-ability". Acrylic is much more forgiving in this regard, and almost any reasonably competent and well-equipped DIY'er can drill acrylic (notice that I said "almost any"? And, by the way- I do NOT place myself in that category! That's what my reef-geek friends are for!), whereas glass really requires skills and equipment that most people just don't have. It's best to order any tank (IMO), especially a glass tank, pre-drilled to your specifications at the manufacturer. You also have to consider the possibility of accidents and, for us So Cal people, earthquakes. I have seen a 48 inch long, fully-filled acrylic aquarium shift right off of the stand, with absolutely no damage following an earthquake. Glass tanks can be downright disastrous in these types of situations. Even if you don't live in earthquake country, do think about other possible issues with breakage, including shipping and transport> 
I have to make my mind up soon so I could order my tank and get it cycling. Thanks 
<Gee.. I wonder if I was more of distraction factor here? Well, do make the decision based on your own set of pros and cons, and go from there. Good luck! Regards, Scott F.>

Glass, Acrylic, etc 11 Aug 2004
Good Day Crew!! <Hi Corey nice to meet you, MacL here with you tonight>
This may not be a question that can be answered but I thought I would give it a shot. <I promise to do my best Corey.>  From all of the opinions and information I have gathered on the glass vs. acrylic tank debate, I have concluded that acrylic is far superior to glass in every facet except the one obvious detractant, its propensity to be easily scratched. <I think that there are people who would argue that point with you. I personally fine acrylic to be best for me and that's what I tell people. Look into both and figure out what works for you the best.>  I believe in the Today's FAQ's yesterday or the day before, one of the crew members mentioned that he had a 300 gal. acrylic tank that was so scratched up, he would never buy one again. <I haven't seen that one but doesn't surprise me. Let me just tell you that I have a 20 year old acrylic tank with no scratches on it whatsoever. Acrylic can also be polished and the scratches removed. If you get a scratch in glass its there permanently. But another option is that Starphire glass which is quite lovely.>  My question is have any of you read or heard of existing or developing material for tank construction that has all the benefits of acrylic but the scratch resistance of glass or better. <There are some stronger types of plexi glass such as Lexan but its very cost prohibitive.> I know I am looking for the utopian tank, but thought it wouldn't hurt to ask. <Never hurts to ask and don't forget there are those innovators who are making takes out of wood and other materials and lining them. I guess my point here is find what works best in your world. Yes be careful with plexi it does scratch. I have a scratch on the inside front of my tank right now that I need to take out but it was my fault. I dropped a piece of rock and it ran down the front. BIG mistake. I do think with plexi that you have to be very careful. But like I said for me the benefits outweigh the costs.> Thank you for time and knowledge <Hope that helps.  MacL>
Corey

Hard aquarium questions
Dear Mr. Fenner,
<Lisa>
I was wondering if you could answer some of my questions about the way aquariums tanks are currently made. I have seen the debate between using glass or using acrylic for the tank but I rarely see any mention of polycarbonite which has been used at Walt Disney World in the living seas.
<Mmm, me neither. I know of the use of this impact resistant material in greenhouses... its order of magnitude strength greater than acrylic...>
I rarely see it mentioned at any of the website businesses making aquariums. It's much stronger than acrylic and so it doesn't scratch. Why don't they use it more often?
<Don't know... have you investigated internet sources of information re this materials properties? Perhaps it bows badly in small thicknesses...>
Also why are the stands often made out of wood when they could be subject to water damage? Why don't they use a design more waterproof?
<Mmm, cost of production, materials... legacy of using wood>
I also have a question about how breeders advertise mailing people certain fish and corals. I wonder if that is safe, or will the sea creature be killed in the process?
<Sometimes>
Also is it truly possible to help the environment through the captive bred programs?
<Not necessarily... I have asked friends/associates in the trade similar questions. What sense does it make to construct artificial "live rock" that utilizes cement made from... corals and their reefs?>
Thank you for taking the time to read my e-mail.
Lisa
<Thank you for writing>

Shaken, Not Stirred
Hi, I'm a devoted fan from Fairbanks, Alaska.  As you may or may not know, we recently experienced a 7.9 earthquake.
<Yikes! Hope that you're okay!>
Until recently, this type of experience has been a rare occurrence, at least at that magnitude.  This last quake left me with saltwater drenched floors and electrical components.  Obviously, I feel fortunate to have sustained such little damage, but the swaying tanks during the quake immediately made my mind race.  With such great interest in the aquarium trade, especially in California, are there measures commonly taken in earthquake prone areas to prevent the toppling of tanks and other associated damage? Thanks in advance, Andrea
<Well, Andrea, as someone who lives in LA, and has been through a few quakes, I can certainly understand your concern! Some of the measures that I have seen aquarists do include actually strapping stands and tanks to the walls(!), utilizing acrylic tanks exclusively (That's the #1 reason why I swear by acrylic, having had one shift completely off the stand by about 18", and still not crack!), GFI outlets, and lots of different bracing methods. I'd recommend doing a search on the internet under "earthquake safety", and you may come up with some ideas (not always for aquariums, but nonetheless applicable) that can help. Do also visit our WetWebMedia chat forum for some feedback from fellow hobbyists. Good luck and be safe!  Scott F.>

Glass Aquarium
Dear sir,
I recently acquired a 105g Oceanic Aquarium w/stand. It is an all glass tank and therein lies my problem. I would have preferred acrylic but am not complaining as I got the tank at a very good price.
<Nothing wrong with glass tanks... and definitely nada bad about a good deal>
Anyway, here it is: I wanted to set it up with the water going down to a sump or refugium underneath the stand and place much of the filtration etc. there out of sight. However, as the tank is glass and is not drilled for that setup in tank, I would have to use an over the edge overflow or whatever. Now that that is my option, I have heard several horror stories about these malfunctioning and flooding the room when the siphon breaks etc.
<Hmm, well... the tank can likely still be drilled if you want to investigate the possibility... but for the money, time, hassle, I'd get/use an overflow box... these are about foolproof... and you could always rig up two... if you're fearful that one might fail... take a look at the spec's of the ones offered on www.cprusa.com>
So, my question is there any way to accomplish the under tank refugium w/o a great risk to my mothers carpet (and thence to me!) or should I do something else. How would you set up a nondrilled glass tank? I had planned to setup a fish and hardy invertebrate system w/live rock, sand-then later perhaps convert to a full blown reef system.
When I decide about a year ago to get into this hobby, I thought that I should first read up on it-so have spent the last year buying and reading books on the subject, and I will have to say that your book is the most well worn of the lot. (smile)
<And a very big grin here>
I feel I have a decent understanding at least enough to get started-I hope! However, the plethora of gizmos and doodads has me somewhat confused anything more technical that a can opener confuses me I must admit!) So if you have any recommendations as to a best setup for my glass tank, I would be eternally grateful...(smile) Regards, Kim
<I'm here to help if you get stuck, would like another opinion or three. Bob Fenner>

Aquariums: Glass/Acrylic?
I would like to know what are the price difference between glass and Acrylic. 
<Depending on? Thickness, quality....? Acrylic costs more wholesale and retail... for practical purposes... a rule of thumb so to speak, a good two to three times as much>
I just read your website and you said you like acrylic better. 
<For most applications, yes>
I'm trying to buy a tank approx 65 gallons. I don't see any acrylic tanks in the pet store in my town so I might have to order one. So also read that if u scratch the acrylic tank it can be remove. We kind of gauze do u have to use to get rid of the scratches? 
<My favorite simple remedy involves pastes of different grits... very fine scratches can be rubbed out with gritty types of toothpastes... But plastics dealers everywhere offer types of technology for this>
Well I will appreciate if you answer those questions. And thank you for taking time to read my email, Aaron
<Be chatting. Bob Fenner>

Aquarium Material Choices
Bob,
<Steven Pro taking my turn answering a few questions this morning.>
I would like to thank you in advance for all of your help. I am looking to make a major step in advancing my reef tank. I only have a 29 gal. glass reef, which I have had for 3 years or so. It is time to upgrade to the 90 gal. range. Do you have any suggestions on glass or acrylic?
<I am going to give you a pretty lousy answer. Bob prefers acrylic. In California because of earthquakes acrylic is required. They are also easier to work with, drilling overflows, carrying do it lighter weight, etc. I prefer the better scratch resistance of glass, cheaper price, and in this area, glass tanks are readily available. Acrylic is consistently a special order product.>
I know the pros & cons of each. After deciding to buy a glass tank, I went to my LFS to price them out. They pretty much told me that glass was a waste & acrylic is the only way to go. Are they just trying to get $$$$?
<I cannot say for sure as I do not know them.>
I like the durability of glass, but is a 90 gal. more likely to leak than my current 29 gal.?
<No>
Is the acrylic really worth the extra money?
<To some people, but not to me.>
I think I would prefer a tank with an overflow, do you agree with this idea?
<Yes, very much so, with either material.>
What is your suggested tank equipment for someone who is interested in stony polyped corals, anemones, clowns, gobies, tangs?
<Sump, high quality skimmer, source of purified water, MH's, DSB, and liverock filtration. A refugium would be great, too.>
Are wet-dry systems not advised for reef tanks?
<Correct. -Steven Pro>