Big, Glass tank owners.... Please help

[lpsouth1978]

We are in the process of setting up a 300DD and are almost ready to get it wet. The main thing holding us up is that my roommate is trying to find the perfect thing to place between the tank and stand. He is VERY particular.

The steel stand has approximately a 1/16" gap in places and he wants to find a foam tape that will help fill these gaps and properly support the tank. He is looking for something like a 1/2"x2" neoprene or silicone tape that could be used as a gasket. I think he is overthinking it and could get away with just a simple foam tape weather sealer gasket from the hardware store.

What have you all used, or what do you suggest? He is driving me CRAZY!!! He has been looking for the perfect solution for almost 2 weeks now.

 

[Dmorty217]

For glass tanks you don't use anything, you only use foam with acrylic. Who built the stand?

 

[lpsouth1978]

For glass tanks you don't use anything, you only use foam with acrylic. Who built the stand?

He did. He is a welder by trade.

 

[A_CoupleClowns]

Glass tanks need to be supported well in all 4 corners. Small gaps along the length between the corners is perfectly acceptable from the research I have done. You can use a pc of plywood between the tank and stand and shim between the plywood and stand to eliminate the gaps between the tank and plywood.

Never use foam underneath with a glass tank. The foam is for flat bottom acrylic tanks only.

 

[dave.m]

Sorry to disagree, but you can use a sheet of thin (like 1/2") high-density foam as used in building foundations insulation for glass tanks, though it is preferable to just lay the tank directly on the board. Going directly on the board puts the onus on creating a level stand instead of expecting the tank to compensate for the stand's shortcomings. The tank's needs take priority, including levelness and evenness.

If the gaps are as small as you say (1/16" or less) see if your welder friend can grind them out. The trouble with tape is that it is uneven and would not distribute load evenly as it is only around the edges.

Dave.M

 

[lpsouth1978]

Glass tanks need to be supported well in all 4 corners. Small gaps along the length between the corners is perfectly acceptable from the research I have done. You can use a pc of plywood between the tank and stand and shim between the plywood and stand to eliminate the gaps between the tank and plywood.

Never use foam underneath with a glass tank. The foam is for flat bottom acrylic tanks only.

Why do you say NEVER? Will the foam cause problems?

Sorry to disagree, but you can use a sheet of thin (like 1/2") high-density foam as used in building foundations insulation for glass tanks, though it is preferable to just lay the tank directly on the board. Going directly on the board puts the onus on creating a level stand instead of expecting the tank to compensate for the stand's shortcomings. The tank's needs take priority, including levelness and evenness.

I am afraid that grinding out the imperfections is not an option. He has already had the stand Powder Coated. You can just barely slide a credit card under some spots. He also does not want to put a sheet under the entire tank, that was one of my suggestions as well. He is footing a large part of the bill for this tank, so he has to have the final say in how it is done.

If the gaps are as small as you say (1/16" or less) see if your welder friend can grind them out. The trouble with tape is that it is uneven and would not distribute load evenly as it is only around the edges.

I believe this is why he was looking at 1/2" foam tape. The tape foam can only compress so far, so it should compress more in the tight areas and less in the uneven one's, thereby filling the gaps and lending more support. It may not be perfect, but better. No?

 

[dave.m]

Tape puts ALL the tank's weight just on the edges instead of distributing it evenly over the entire bottom surface. I think this is why people are hesitant to suggest any kind of foam under glass tanks - it gets used as an excuse not to fix the stand where the original problem(s) starts.

Dave.M

 

[ca1ore]

Why do you say NEVER? Will the foam cause problems?

The prevailing wisdom is that foam is unnecessary in a rimmed tank (i.e. one that does not sit flat on the full surface of the bottom panel) and at best does nothing. If the tank does sit on the full bottom, whether glass or acrylic, foam is almost always required by the manufacturer. Marineland do not recommend the use of foam on their tanks. Done improperly, foam can put pressure on the bottom panel and cause it to fail.

Having said all that, I do use foam under all my tanks, including my current Marineland 265. ML told me that foam could damage the center brace on the bottom - only there is no center brace :lol: I use the 5/8" ridgid pink foam that I get at HD, and it has always worked fine for me (25 plus years). The tank doesn't sink into it all that much - maybe 1/8" - so there's no chance of it pressing on the glass bottom.

Caveat emptor!

 

[lpsouth1978]

Tape puts ALL the tank's weight just on the edges instead of distributing it evenly over the entire bottom surface. I think this is why people are hesitant to suggest any kind of foam under glass tanks - it gets used as an excuse not to fix the stand where the original problem(s) starts.

Dave.M

That would make sense if the bottom glass was sitting directly on the stand, but the 300DD has a plastic rim around the bottom and the bottom piece of glass is raised 1/2" off the stand, even if the tank is on a board. In this case, the edge is the only thing supporting the tank as it is.

 

[dave.m]

If it is built to withstand the weight on the edges only then check to see how the manufacturer's stands are built and match accordingly.

Dave.M

 

[Moser]

My 6ftx8ftx3ft glass tank sits on 1" polystyrene foam. That rests on a 1" plywood base, which sits across 8 Steel joists.

It has a double 3/4" glass base. Each layer of the base is in 3 pieces, all siliconed together inside a steel brace. The brace rests on the foam.

Mo

 

[A_CoupleClowns]

I take that back! Sounds like you can put glass tanks on foam. Just goes to show there is more than one way to do it.

Good luck!

 

[Dmorty217]

I too was unaware that foam could be used with glass tanks. Makes sense now that I think about it

 

[Hal]

I too was unaware that foam could be used with glass tanks. Makes sense now that I think about it

Miracles recommended foam under my glass tank from them.

 

[risin]

I have a 250DD sitting on 3/4" plywood and 1/2" foam which I highly recommend. I feel that it ensures even contract around the perimeter.



The most important detail is to make the tank perfectly level from corner to corner in all directions. Don't take any shortcuts in this process.

 

[slief]

Never use foam underneath with a glass tank. The foam is for flat bottom acrylic tanks only.

That couldn't be further from the truth. Most rimless glass tank manufacturers will VOID the warranty on the tank if you don't use foam between the tank and the stand. Especially if you are using a stand not made by the Mfg. Unless the tank has a rim on the base that is designed to support and distribute the weight, you should absolutely use proper foam between the tank and the stand. The slightest imperfection in the stand can cause a stress point in the bottom panel which will break the glass. The foam helps mitigate any imperfections or high spots in the wood.

If you don't believe me, take a look at the warranty policy and FAQ from manufacturers like:

Glass Cages:
http://www.glasscages.com/?sAction=AqWarrantys

Reef Savy:
http://reefsavvy.com/faq/

Miracles Aquarium:
http://www.miraclesaquariums.com/custom_tanks.html

Mr. Aqua Aquariums:
http://sevenports.com/warranty/

Need I say more.

 

[A_CoupleClowns]

That couldn't be further from the truth. Most rimless glass tank manufacturers will VOID the warranty on the tank if you don't use foam between the tank and the stand. Especially if you are using a stand not made by the Mfg. Unless the tank has a rim on the base that is designed to support and distribute the weight, you should absolutely use proper foam between the tank and the stand. The slightest imperfection in the stand can cause a stress point in the bottom panel which will break the glass. The foam helps mitigate any imperfections or high spots in the wood.

If you don't believe me, take a look at the warranty policy and FAQ from manufacturers like:

Glass Cages:
http://www.glasscages.com/?sAction=AqWarrantys

Reef Savy:
http://reefsavvy.com/faq/

Miracles Aquarium:
http://www.miraclesaquariums.com/custom_tanks.html

Mr. Aqua Aquariums:
http://sevenports.com/warranty/

Need I say more.

Looks like your right and I am wrong :debi: :lmao:. Being wrong every once in awhile is all part of life though, I have found that out the hard way a few times lately.

Anyway if you look 5 post up at post #12 you will see I said this below about my first comment.

I take that back! Sounds like you can put glass tanks on foam. Just goes to show there is more than one way to do it.

Good luck!

Bottom line is thanks for making sure the truth was stated. Sometimes people research RC and find mis-information that others (who seem knowledgeable) have posted and think they have found the correct information (like in my case above). Then someone in "the know" has to set the facts straight. FWIW, AGE who is building our glass rimmed 470g, told us not to use foam and to use plywood only, so there must be a few different ways to handle this situation. Since the OP has a rimmed glass tank, I thought he was supposed to avoid using foam. I was just trying to help out, but shot myself in the foot again apparently :lol2:

 

[nuxx]

Have a small gap on one edge of our 150 gallon frag tank.

Putting the tank of extremely straight 1/2" ply, then putting foam between the ply and stand.