marineland rimless tank + foam, not recommended by perfecto support?

[amagad]

Just got Marinelands 20g rimless aquarium with stand which is not perfectly flush exactly like what my 37g is experiencing. I called them to verify if they recommend I put foam, they said they do not condone it. That if I purchased the stand with aquarium, there will be no issues even if I do see gaps.

Should I go against the grain with their answer and move forward with foam install? I bought 1/2 inch Ensolite foam in preparation just in case. I've read 3/4 but that seems way too thick for such a small tank. http://foammart.com/closed-cell/ensolite/

[Betta man]

It does not matter if it's perfectly flush. The tank is made to resist lots of pressure. It's your call, but I don't think it's necessary.

[emc7]

I've seen different manufactures recommend foam and avoid foam. Glass cages tells you to use it. In theory, the tank will sink into the foam enough to sit level. What you don't want is uneven pressure on the bottom. If you put foam inside the bottom rim, you could conceivably push the tank out of the trim. IME 20s are very sturdy and are not likely to give you any trouble. The higher tanks, though, like the 37 and 29H are the troublemakers. And I never want a tall hexagon again.

I would go with the maker of your specific tank, so if you ever have to make a claim, they will be more likely to honor it.

It may be that weight of the water in the tank itself will smush out the lumps in the stand after a few weeks.

Send them a picture of your gaps, and see if there is anything they can do for you (like send you a new stand top)

IMO, what matters is to have the water level level. I would shim under the stand (not the tank) until you have this and not worry further.

[blindkiller85]

Emc7 does make a fair point by saying to go with what your manufacturer says. They should honor it if you're doing what you are told to by them. Or request a new stand or top.

I personally would NEVER recommend foam for a fish tank. Foam can settle one way and level out and over time keep sinking. But the problem is it's still not level on the bottom of the tank. Because that corner that sunk in still has more weight on it, otherwise it would all sink in. But if that happens that the lumps in the stand are settled out by the weight of the water that would be best. But it might not happen.

Granted, I don't have a rimless, but my 125 has been up and running since before I joined this site and it's been unlevel the whole time and no problems. It's about 3/8 of an inch unlevel, which is huge when you start talking about weight of water, 175 lbs of gravel, other decorations, and cleaning. Should be around 1300 pounds. Tank was made in 2005 with original seals on it.

I have no illusions that I could have problems. But I understand thoroughly about weight distributions from my studies in structural engineering. Solid surfaces will always distribute weight much much more effectively than anything that can or will compress like foam, or carpet and so on. Wood and composite materials will compress at a rate that is not effective to measure in any certain amount of time.