why foam?

[mycat99]

i have a question on why do some people have strofoam under there tanks and others dont?is it needed or just something you use on larger size tanks

[kien]

It is a good idea, especially on larger tanks and/or tanks that don't have a trim on them (bare glass on stand surface). If you happen to have something like a speck of sand, dirt, debris under the glass or even just unevenness of the surface that you are putting your tank on that is a single pressure point that could stress that bottom pane of glass. Over time it could cause issues. The foam at the bottom helps to cushion and even things out under the tank.

[banditpowdercoat]

Yup, to eliminate pressure points. Not needed if tank has trim on bottom and glass sits off stand

[soapy]

If you use foam but find it ugly just paint the edges with any acrylic paint. Mine looks like it is almost part of the furniture.

[sphelps]

I use rubber sheet on flat bottom tanks (no trim) which is all you need provided your stand is flat.

[mr.wilson]

In my opinion the idea of styrofoam "leveling a tank" is a myth. The compression strength required to compress styrofoam (dense blue/pink or more pliable white) is not met with a tank even if it is off level and very large. The weight is spread out evenly so the tank will remain off level and the tank will be as level as the stand below it.

I use 3/4" plywood to spread the weight over the stand and support the bottom to minimize deflection. tanks with holes in the bottom are particularly weak in this respect. With glass tanks I use 1" blue styrofoam over the plywood to preserve the tank warranty, but I only do it to make the manufacturer happy.

The only benefit of styrofoam under the tank is to guard against imperfections in the stand or plywood directly under the tank. As sphelps has suggested, rubber works just as well and it's cleaner with a lower profile. It's impervious to solvents and physical abrasion. In the end you have to do whatever it takes to make your tank manufacturer happy so he honours the warranty.

[banditpowdercoat]

Even if it could be compressed, a unlevel tank would have more water on the low side, and more weight, resulting in more foam compression, and making tank even more unlevel

[kien]

Originally Posted by mr.wilson

In my opinion the idea of styrofoam "leveling a tank" is a myth.

Hmm.. I have never heard anyone suggest that foam under a tank will level it.

[whatcaneyedo]

A little while ago I was in our LFS and they had this 180gal tank with a cracked bottom sitting on an uneaven metal stand (I bent down to the floor and could see big gaps). I guess someone had bought it, brought it home and began filling it up sitting on the bare stand with no foam underneath. It cracked and started flooding his house right away or overnight...

[JDigital]

Originally Posted by kien

Hmm.. I have never heard anyone suggest that foam under a tank will level it.

Neither have I... only recommended/used it to relieve pressure points.