To Styro or Not to Styro?

[vfc]

“Wood is always changing but styrofoam is not the be all end all answer.”



Closed cell foam mat is the be all end all answer.


I don't plan on taking down any of my tanks just to re-level them.

 

[malawi mayhem]

Waste...

mm

 

[Pharaoh]

Pharaoh,
I'm worried about the advice you are giving on this forum. To demonstrate twisting force, take 12 Volt's Man's empty 150G tank, put it on a perfectly flat-level stand and place a silver dollar on the front left corner. You will notice that the rear left corner is now off the stand about the same distance. Now fill the tank with the usual gravel, rocks, and water. You will notice the rear left corner is closer to the stand then it was when empty. That is a twisting force and the cause of most leaks, cracked glass, and cracked frames.

Now empty the tank, cut a 3/4" closed-cell mat into strips and place them on the outer perimeter of the stand and under any plastic bottom braces the tank may have (a 150G has one center brace). Since the foam is on the perimeter it will not push up on the glass bottom. Now place the silver dollar on the front left corner (on top of the foam). Now fill the tank with gravel/rock/water. You will notice the silver dollar harmlessly sinks into the foam and the rear left corner of the tank is making full contact. "Twisting force has been eliminated by foam".

Please do not worry about my advice, I have never stated that I was an expert, but I do understand the forces that we are addressing and the rate of compression of foam. I also fully understand what a twisting force is.

To clarify your point. You are speaking of a focus point in which something is underneath. Yes, the foam may counteract a portion of the silverdollar, not all, but enough to remedy the situation. Now, to further explain this, if a a tank is unlevel and sitting higher in one corner. Please exclude all quarters and such. foam will not compress more to make up for this difference. Foam or no faom, the tank will still be higher on one end.

 

[Tropical Dude]

A self-leveling compound would be ideal, but very pointless unless doing something like a 500 Gallon all glass tank, and at that point, foam would be the least of your stand concerns.

 

[vfc]

“Posted by Pharaoh ..I do understand the forces..”
Good; now you should also understand the ranges we are dealing with. A wood stand on a wooden floor may typically have one corner anywhere from 0 to 1/2" higher (relative to the other three). Any more than 1/2" would be quite obvious to most non-engineering people that something is out of skew.

If you have the proper density 3/4" closed-cell mat under your tank's frame perimeter, than a tank can survive one corner being 1/2" higher. The foam under the high corner would be compressed ~80-90% and the corner on the same side may sink 10-20% into the foam. Will that side of the tank be higher than the other side? Possibly by a small amount (far less than 1/2"); but remember the foam is NOT there to make the tank level side to side or front to back; it is there to keep the "up forces" relatively even on the tank frame thus minimizing the twisting force.

Same concept applies to a car. If you drive over a 3" brick, the shocks compress and the car frame around the wheel only moves up a small amount. If you weld your shocks (tank with no foam) and run over a 3" brick. The side of the car will be 3" higher and the frame under a severe twisting force.

 

[12 Volt Man]

let me get this straight:

what you are saying is that if:

you set up your tank on a wood stand

on a wood floor, shim and level the tank properly so it is planar to the floor etc.

that no matter what your tank is still going to experience a twisting force over time because the floor and the wood sag/warp over time?

if that was the case, there should be a whole lot of broken/leaky tanks out there..

but there isn't that many..there are some, but as I said earlier, I think it has to do with buying used tanks that have been drained, filled, moved, dried out etc..

or due to buying not so great made tanks..cheaper is not better

 

[Pharaoh]

If you have a corner that is 1/2" higher than the rest, you have a leveling issue that needs to be addressed. Stands should be level. If you have flooring that is sagging, drooping or bowing. they you should be addressing the factors that are making thing uneven. Not using foam to try and compensate. If you have the aformentioned issues, you probably should have a fish tank sitting on that spot if it is causing it to sink. If it is an issue of the floor settling. The entire setup should be drained and re-leveled.

Using stand for the example that you gave might in fact reduce a small amount of the twisting force, but it will not fix it like it should be. Even when looking at it from that point. Most glass tanks are engineerd to withstand a small amount fo twisting force in the first place.

The bottom line, nothing works better than a properly level stand. If you do it right in the first place and level your stand, there is absolutly no benifit of using foam.

 

[12 Volt Man]

If you have a corner that is 1/2" higher than the rest, you have a leveling issue that needs to be addressed. Stands should be level. If you have flooring that is sagging, drooping or bowing. they you should be addressing the factors that are making thing uneven. Not using foam to try and compensate. If you have the aformentioned issues, you probably should have a fish tank sitting on that spot if it is causing it to sink. If it is an issue of the floor settling. The entire setup should be drained and re-leveled.

Using stand for the example that you gave might in fact reduce a small amount of the twisting force, but it will not fix it like it should be. Even when looking at it from that point. Most glass tanks are engineerd to withstand a small amount fo twisting force in the first place.

The bottom line, nothing works better than a properly level stand. If you do it right in the first place and level your stand, there is absolutly no benifit of using foam.

I would agree.

 

[12 Volt Man]

saw this comment over on reefcentral about why tanks with braced trim bottoms (like mine) do not require foam nor recommend it:

That's the point of that trim. The glass sits up off the surface of the stand, and small inconsistencies are not an issue. A lot of the stands built by the manufacturers only have a perimeter to lay the tank on anyways, so there wouldnt be any use for that foam. If the tank is designed to sit in a trim (which these are), then placing it on the foam may compress the foam around the edges and eventually put pressure on the bottom pane of glass, potentially leading to uneven support a failed seam

the poster was putting foam on a level stand to 'even out any inconsistencies" between the tank and the stand..

 

[vfc]

Posted by Pharaoh..” The bottom line, nothing works better than a properly level stand. If you do it right in the first place and level your stand, there is absolutly no benifit of using foam.”


Let's make an assumption that 80% of the people measure and shim the stand until it is perfectly flat (all four corners equal height). We could then assume 20% of the tank setups have a high potential for a twisting force.

Take the other 80% who align their stands perfectly flat. When they fill the tank with water; ~ 500 to 2,000 lbs of weight is now pressing down on the stand and floor. How many of those perfectly flat stands are still perfectly flat? How many are still perfectly flat 6 months later?

What are the signs of a stand and floor that have shifted and/or sagged and the tank is under a twisting force? Signs that I have seen are: tank wall bows out (or in), center brace breaks or bows up, plastic trim breaks, gaps form between the tank and stand, seams leak, glass cracks, or glass shatters. These symptoms can occur immediately or months later.
Do a search on this forum for the symptom keywords I mention above, you will find many more people have twisting forces at work on their tanks than you think.

I don't have to worry about any of those because I use a closed-cell foam mat under my tank.