To Styro or Not to Styro?

[Pharaoh]

could you validate the idea that foam, if pressed between glass that is supposed to be "floating' and the stand can lead to a cracked bottom? as I mentioned in my earlier post. I have seen that stated many times - that foam is not recommended for today's modern braced tanks with a 'floating' bottom where the glass is not in direct contact with anything since only the plastic brace/trim are in contact with the stand. it is recommended with acrylic tanks where the whole bottom must be supported..

just want to sort through what is fact and what is a common myth..

thanks..

First, by saying floating glass, I assume you mean tanks with plastic trim and the glass is therefor elevated or floating.

I am going to go out on a limb here and say that in most cases, foam used under a tank with plastic trim is neither useful nor harmless. I say this because most people will tend to use high density polystyrene for the tanks. The rate at which this styro compresses, generally wouldn't compress to the degree to which it would need in order to put undue pressure/stress on the glass. This is not to say that breaking the glass on the tank would not be possible. I think it would mostly depend on the size/weight of the tank, the thickness fo the foam, and the actual compression rate of the particular styro.

I will see if I can come up with a drawing to help illustrate.

 

[12 Volt Man]

First, by saying floating glass, I assume you mean tanks with plastic trim and the glass is therefor elevated or floating.

yes, thats exactly what I mean.

 

[12 Volt Man]

check out this discussion:

http://www.cichlid-forum.com/phpBB/viewtopic.php?t=181637

note the discussion on what I was talking about with the foam pushing up on the bottom glass causing a crack..

 

[12 Volt Man]

Glass tanks technically only need support under the corners, but the longer the tank, the more
support is needed along the length of the long edge. The underglass does not need any support.
The glass is double pane on the bottom for strength. The Oceanic and All-Glass 6 foot tanks'
bottoms can hold up to 10,000PSI, the 65, 75, and 90gal tanks can handle about 8000PSI.
As long as the stand is level there is no need. Foam, if misused can cause an uneven surface along
the edges of the tank and so for liabilities sake, we do not recommend it. It is sort of a "hobbyist trick"
that does work if done right. We as a corporation cannot advise on correct methods of its use.

Regards,

Rob M.
Product Lines Tech. Support Dpt.
Central Aquatics

from that thread. it seems Aqueon/Oceanic do NOT recommend the use of styro on their glass tanks....

 

[Pharaoh]

I will comment here... just my thoughts.... most tank manufacturers do not recommend anything besides thier stand and their tanks...oh and of course only use the filters and products they sell.

If I was to just make a decision based on what I have read and heard I would have to say that styro would not cause the tank to crack underneath. He said it himself..
"The Oceanic and All-Glass 6 foot tanks'
bottoms can hold up to 10,000PSI, the 65, 75, and 90gal tanks can handle about 8000PSI. "

If a double pane piece of glass can hold 10,000 PSI, then what would it hurt for a piece of foam to be touching the bottom of the tank. Even when pushing on the center brace underneath the tank, the pressure would be somewhat spread out. I just can't comprehend a tank being able to hold that much weight, but pressure from a piece of foam will break the glass? A little hard for me to swallow.

Thoughts?

 

[12 Volt Man]

but the foam touching is not the problem. its foam being pressed down between the tank bottom and an aquarium stand.

such that the foam is pushing back UP on the bottom glass.

the glass that is 'floating' is not designed to have pressure exerted from both sides (water in tank above, tank stand/foam from underneath..)

this is what can lead to a cracked bottom, according to many people out there...

 

[NOLAGT]

Great thread yall. After reading it...I think I am still going to use styro tho on my glass 240. But thats becasue the bottom plastic trim is maybe 1/16" or 1/8" at the most....and I might just take it off all together. So it will be sitting on a full sheet of wood like a acrylic tank...I think thats what glasscages says to do anyway.

 

[Pharaoh]

but the foam touching is not the problem. its foam being pressed down between the tank bottom and an aquarium stand.

such that the foam is pushing back UP on the bottom glass.

the glass that is 'floating' is not designed to have pressure exerted from both sides (water in tank above, tank stand/foam from underneath..)

this is what can lead to a cracked bottom, according to many people out there...

I completely understand that part and I agree. I am just trying to rationalize out loud what is going through my head on this one. It gets complicated because of the different "stress" points. The one thing I do know is that it would truly depend on how large the tank is. Smaller tanks would probably not put enough pressure to make the standard closed cell foam touch the bottom.

What is baffling me is this though in comparison. If you stood a board staight up in the air, then had two people push on opposite side of the board, the board would stay stationary. The question then goes, would the foam almost assist the glass by reinforcing it? I agree that inconsistencie in the foam my cause an uneven distribution of force, possibly leading to glass failure/fracture. This maight also happen on a rimless glas tank. This is a great issue to identify.

 

[zennzzo]

SET UP INSTRUCTIONS
All aquariums must be set up on commercially manufactured stands only. A sheet of 3/4" Styrofoam (reaching completely side-to-side and front-to-back) must be placed between the tank and the surface of the stand. Aquariums should not be set on wood furniture, stereos, televisions, or other surfaces that have not been designed to support an aquarium. Setting up the aquarium on a homemade stand or on a surface such as the ones mentioned above can result in stress breakage of the side or bottom glass panels of the aquarium. Breakage is NOT guaranteed. It is very important to follow the INSTRUCTIONS:

• Each leg of the aquarium stand must sit flat on the floor.
• Each corner of the aquarium must sit flat on each corner of the top of the aquarium stand.
• If either the legs or the corners of the aquarium do not sit flat then proper shiming is required. The shimming referred to here is the placing of thin strips of tile, wood, or paper under the leg or corner of the aquarium to make the leg or corner sit flat.

IMPORTANT!!
Special setup is required on a carpeted floor due to the fact that carpeting tends to cover up uneven floors which can cause stress breakage. If the aquarium is set on carpeting, the carpeting should be pulled back to expose the bare floor. Then follow setup instructions above. After the stand and aquarium have been checked and proper shiming done, if necessary, the capeting can be put back in place and the stand and aquarium should be placed in the exact same position as before on top of the capeting. The stand and aquarium should be reset up using the same shims, if any were needed, in the same position that was used when the stand and aquarium were set up on the bare floor.

not too sure about how strong their tanks are, but if they are average then this might prove to be good info...

 

[NOLAGT]

This is how my 240L is built from them....built like a tank yet hard to hit...icecube and ezey-e co runnin ****. Sorry couldnt resist.