[Rin]

Ninong,

Here is the thread everyone is referring to:

http://www.reefcentral.com/vbulletin...threadid=48764

[Ltspd]

After reading the thread on RC I still find it hard to blame the styrofoam. Easy to blame things on something other than the used tank. I cant remember did the article date the tank? Who made the tank? To me it sounds ad if the tank was out of level enough to cause the water force to be more outward than down. The use of foam is in addition to, after leveling the stand. If the guy used a construction board (not real specific) and not pink or blue board that could very well be his problem. If it was the fiberous board (name slips me) and it got wet then I could see why it would fail.

All I can say is I have it, 3 local reefers in my area use it. 360g, 240g, 180g tanks respectivly. The 360g guy is my mentor and has been in the hobby for the past 20 years. You may have seen his tank as the cover for this years MACNA. All the starphire tank owners have it under theirs (IA). The custom tanks at a local LFS use it under there tanks. Its recommended in 2 books commonly suggested to new hobbiest, of which I did not realize. From a engineering standpoint it makes perfect sense. Guess we should all remove it or just consider ourselves lucky.

[Ninong]

Rin,

Thanks for posting the link.

If I understand him correctly, I believe what he is saying is that he used 1" thick styrofoam of the highest density--what he calls construction grade--and cut it to fit under the glass bottom of the tank, but not under the frame. He doesn't exactly say that, but I believe it may be what he did. Is that the impression you got?

If that is the case, then he is probably correct in assuming that the styrofoam caused his problem, or, more specifically, the way he used it caused his problem. With acrylic tanks, the load is evenly distributed across the entire bottom of the tank. With glass tanks the load is evenly distributed along the perimeter of the tank--the frame. I wonder if he managed to elevate the rear of the tank so that the frame was not actually bearing the load, only just barely making contact with the stand?

My advice would be that styrofoam, or some other cushioning material, is an excellent idea for an acrylic tank. For a glass tank, I would say that no matter what you decide to do, be sure that the weight of the tank is evenly distributed along the entire frame of the tank--with or without a pad under the frame. When I had my custom Starphire glass tank built, I requested a styrofoam pad be attached to the bottom, although, as I said in my much earlier tank thread, I did not think it was actually necessary. Now that I am getting ready to install my tank, I will be extremely careful to make sure that the frame is in full contact and that the load is evenly distributed along the frame and not the bottom of the tank. If the styrofoam seems to be causing any sort of a problem in achieving that goal, I will ditch the styrofoam.

I would like to add that I have seen pics of several beautiful glass tank installations in the members' tank pics sections of the various boards where the tank is placed on the standard open top stand with a strip of styrofoam running all around the stand to support the frame of the tank. If that is the type of stand and the type of installation that the guy with the blown tank had, then I really don't understand how it happened.

Ninong

[Ironreef]

Just because alot of ppl do it doesn't mean its right. But IMo if you were to use styrofoam of padding I would only use thin not thick. You should be able to set up your tank withing 1/4" unless you have really bad floors or a poor built stand. But styrofoam with ply wood like some ppl with large tanks use i would think is better. But for me i just don't loke the look. If it was hidden maybe. But imo if you can level your tank within 1/16 over 4-6' it's just as easy to shim. And even if you don't I still think it would still be stronger = no give.

[Starmstr]

Luck has nothing to do with it. As an engineer we design falsework foundations and large bridge pours using the same methodology by placing Styrofoam under the fluid PCC.

OPINIONS make fools of many. Informed decisions are the building blocks of knowledge.

[BigLar]

The styrofoam I had was the 1" white stuff from HD. One of the problems I had with the styrofoam was getting the tank perfectly level. I think it was because the styrofoam was so thick. I leveled the stand with shims first. As I filled the tank, the tank would be level but then shift. When I took out the styrofoam from under the frame of the tank, I didn't re-level the stand and it is now perfectly level.

I think I made the right choice. Although, I believe that 1/4 or maybe even 1/2" styrofoam would be fine.

[Ironreef]

Originally posted by Starmstr
Luck has nothing to do with it. As an engineer we design falsework foundations and large bridge pours using the same methodology by placing Styrofoam under the fluid PCC.

OPINIONS make fools of many. Informed decisions are the building blocks of knowledge.

Whats PCC? My question is you want the columns to move for expansion? Or what ever the member is. Those are rigid items with all the rebar. If it has post tension it's made to move. I doubt a tank is rigid enough to handle shifting. Or it's not designed to shift. Not saying the tank will move or shift. But that hard styrofoam what most ppl use from HD is for insulation. Not for holding weight. FWIW I worked on a few bridges myself and never saw styrofoam unless it was an expansion joint made to move. But they may build them different here.

[Ltspd]

BigLar, you made the right move by removing that type of styrofoam from under the tank. Had the correct stuff been used (blue/pink board) it would have not been necessary, and you would have benifited from it capability. Somehow I feel that the guy on RC may have made the same mistake as you almost did. The stuff you are refering to looks like the cheap beer cooler material, and has no load carring capability.

IronReef, have you never lined a foundation with isolation board? It may not be used in your part of the country but here I have done so on several occasions. It is used for heavy, vibrating equipment. I have used it on large grinders in particular. When you have a very heavy machine that requires a deeper than normal foundation the ground, sides and even the first pour are lined with what I refer to as this isolation board. This isnt the same stuff as the black board that was common in house construction (Its been replaced by the pink/blue board here) This is a very dense rubber mat that seaperates the foundation from the rest of the floor /earth. It allows the foundation to float and not be effected by the suronding enviroment. When I say float its not to the point of being able to physically push the foundation/machine on its footing.

I also used this principal of isolation when I worked for Newport News Shipbuilding. This is common mounting practice on submarines when noise transmitting machines were mounted to the structural foundations I designed. They were refered to as DIM or RES mounts and were nothing more than rubber sandwhiched between the machine and the hard mount. They handled large loads, and permitted any vibration from escaping the machines. This was to keep the subs quiet and also allow some expansion and contraction without effecting the machine itself.

[organicreefer]

people have been doing it for years ,i know,and a couple books that i have suggest it as well,but regardless,dont you guy's think the builder's know their own products?im sure there is a reason they say not to put youre tank on a "cushion",if it worked better why wouldnt they reccomend it?
before i set up my new tank i looked into it ,the guy's at oceanic said no way,not pink or blue ,not even an 1/8th of an inch,its not neccesary ,and if anything ,could cause a problem.
ill continue to pass along the advice that the manufacturer has given me ,and others.place youre glass tank on a smooth, hard, level surface.

[ReefHog]

OK, I hate to see threads get too lopsided. I have a 125 AGA that has been on a 1/2" sheet of white styrofoam for over 8 years. And it has been taken down and set back up three times in those years using the same styrofoam (due to moves). I decided to use it because I made the stand myself out of 2X4's and although I seemed level and true, I didn't want to take any chances. The styrofoam is under the whole tank..frame and all. The few times I took it down the impression it made in the styrofoam was less than a 1/16 of an inch anywhere. All that weight and such a small impression. Anyway, When I move to a larger aquarium (soon as my Green Moray is almost two feet now) if it's glass, I will probably not use the foam and instead put more effert into making a better stand. However if I reuse the 125 AGA, I will reuse the foam as I havn't had any problems and why correct something works.

Bottom line, If the stand is made professionaly or at least by someone who knows what he is doing, then styrofoam is not necessary IMO. But I don't believe it would do any harm either. Just not necessary.

[Ironreef]

There maybe styrofoam that can be used in heavy construction for support I just never seen it that way. Doesn't mean they don't use it. But the stuff at HD is for insulation and sound as far as i know. Most construction I work on they don't undersize anything they seem to over build it.= 100t footings full of 11-18 iron rebar ect.. So I won't say it can't be used just if one were to use it make sure it can handle load applications. But then one would think if it was able to handle load applications smaller tankes wouldn't benifit from it? They wouldn't be heavy enough? Unless we are talking .001+/- Hmmmm than not on my tape