Foam under tank?

[Aristarchus]

I bought a sheet of insulation styrofoam from HD the other day and put it under my 55 gallon tank I am setting up.. I was wondering if I should have cut the sheet to come out from underneath the edge of the trim by a 1/4", so it won't collapse on one side and make the tank lean... I just realized this after closer examination, if anyone has any input as to wether or not I should keep it the way it is please feel free.

BTW I haven't put any water in it yet just to be sure!

 

[artful-dodger]

I've personally never seen much value in the padding layer but it could help if there's any small irregularities in the stand surface. My suggestion would be to center it on the foam (sticking out from all sides), fill the tank and then trim the foam with an exacto knife. If you try to line it up and then fill it I'm guessing that it will squeeze out a bit and need to be trimmed anyway.

Just a thought (with no experience)! G'luck

 

[Aristarchus]

After thinking about it even more, I think I might have to go buy another sheet... I'm just worried that it might compress and slide underneath the trim.. thanks for the reply btw

 

[bllfish]

Instead of the styrofoam buy some of the dense rubber flooring pads at Home Depot. They are 24" X 24" and can be joined together. I have them under my 72 Bowfront and they work fine. They are not very expensive and I also have them under my sump to help with any pump vibration etc.

 

[Agu]

If it's a glass tank don't use the styro. Glass tanks are designed to be supported on the edges. If the styro compresses at the edges and puts pressure on the bottom glass it can crack the glass.

If it's acrylic a thin sheet of styro (1/8" ) can help to even out pressure along the entire bottom.

 

[rpeeples]

interesting.

 

[roons]

im not sure what you guys are talking about, a piece of styro under a tank is going to have the same amount of pressure put on it on all areas, the total weight of the tank is spread out over the total surface area.........................just how is styro going to collapse in on itself if its a full sheet with 1500 lbs on top of it?

i put a 1" thick piece under mine, glass tank, no worries here

 

[bllfish]

I think the glass tank has an edge that extends below the glass bottom. If the material you are placing under the tank on is too thick, the edges of the tank can compress the material under the edges so the edge sinks into the material and the center of the could press up on the tanks glass bottom.

 

[roons]

ok, say indeed the glass is 1/8", 3/16'? even 1/4" ? higher than edge of tank, when you fill the tank the outer edges will sink into foam until foam hits glass, then everything will sink at the same rate with the same amount of pressure.....................what do you think , the outer edges will sink faster than the middle causing stress to the glass? after the edges sink initially its a flat surface with same amount of weight on it all..................................


"do the laws of physics cease to exist on your stove? were they magic grits? did you get them from the same guy jack got his beanstalk beans from?"

 

[bllfish]

True, but the bottom glass was not made to take as much stress as edges. That is why the edges extend below the bottom glass and support the bottom and sides. As the tank sinks the pressure of the material would push the bottom glass up wouldn't it putting stress on the silicone seal?

 

[roons]

the pressure exerted on the glass from the foam upwards is the same as the pressure exerted on the glass downwards from the tank contents, uniform , across the total surface area of the glass.....................thats the whole point in using foam, to ensure a pressure "point" isnt created...............im sorry , i cant continue this , i have to take this foam call

 

[hans1976]

Agu is 100% correct. And if it is an All Glass tank, I believe it voids all warranties.

 

[bllfish]

I agree roons - thanks for the info.

 

[Silencer]

Most glass tanks have plastic braces across the bottom just like they do across the top. This would be stuck between the foam and glass and create a pressure point, breaking the bottom.

HOWEVER, I would also like to point out that even though it only touches around the edges, that black trim on a tank actually has a decent amount of surface area. The actual pounds per square inch that the black trim exerts on the surface it rests on is so low so unless you use a really soft/crappy kind of foam it simply isn't going to compress like that.

The 1/2" pink insulation foam I have under my AGA 180g and AGA 125g has not compressed AT ALL. The only reason for the foam is to prevent any pressure points caused by an uneven stand surface or any small foreign objects that somehow got under the tank.

 

[XeniaMania]

Interesting indeed

 

[roons]

i used the 1" stuff you use on houses under siding, i never thought of the brace , i have an aga 120..............i didnt notice if it had the brace , still not worried however