Foam under a SeaStar tank?

Aquattro · #1 12-25-2010, 06:17 AM

Quote:

Originally Posted by Borderjumper

I sure would feel much better if I could pinpoint the cause.

That's tough. Lots of people use foam, and lots use wave makers. The foam theory does make sense though. How much compression was there? Enough to force the contact between glass and foam? Thinking back, my 155 sat on a framed stand, no solid top so foam only contacted the edges. I never sit my tanks on a flat surface, so foam would work fine for me.

Borderjumper · #2 12-25-2010, 06:27 AM

Yeah the glass was defiantly sitting down onto the foam.. The edge of the tank had compacted down into the foam at least an 1/8 of an inch, putting the glass right on the foam,that's why the water didn't just gush..the foam was exerting pressure kind of holding it together. If a tank is not designed to have the glass carry any weight, and it's in contact with rigid foam.. It's carrying weight. If it woild have been soft foam.. Then I would think it would have just kinda of supported the glass.. Hard foam has no give.. So the glass was actually being pressed down on it..

Foam and the pink insulation foam may be two different things in this application?? Think of the foam floaties that corals come on.. It's hard and doesn't have much give.

Aquattro · #3 12-25-2010, 06:36 AM

Sounds like you've got your cause then. Still crappy!!

Borderjumper · #4 12-25-2010, 06:51 AM

heres a picture I took of a piece of the foam we removed.. it may explain better than I can in typing.. see how the rim sunk into the foam all the way around, leaving the glass in contact with the foam. The farthur the rim goes into the foam.. the harder the glass presses into the foam.

StirCrazy · #5 12-26-2010, 04:22 PM

one problem with your explanation here.. once the foam touches the glass then there will be less force on the edges and the trim will not be able to sink any farther, so in theory there is no way the foam can push up against the middle of the glass.. also judging by the picture I would say the middle of the glass wasn't even touching the foam. there are to many rough marks and such that would have all been smoothed out by any contact.

Steve

Quote:

Originally Posted by Borderjumper

heres a picture I took of a piece of the foam we removed.. it may explain better than I can in typing.. see how the rim sunk into the foam all the way around, leaving the glass in contact with the foam. The farthur the rim goes into the foam.. the harder the glass presses into the foam.

imisky · #6 12-25-2010, 06:54 AM

hey Shelley,

It was quite a shock when Paul told me about the tank, so as Paul has mentioned tanks with floating bottoms should only be supported by the trims and should never be put on foam in any situation. The result is usually what happened to your tank

This is usually the case with tanks built with the 4 side panels sitting on top of the bottom glass. These shouldnt sit on foam as any pressure on the bottom will push onto glass that doesnt give much before snapping or in your case cracking.

Tanks thats built with the 4 side panels sitting around the bottom glass has a little bit of a flex if theres any pressure pushing up on it as the silicone holding the bottom panel to the 4 sides will flex as the bottom pannel gets pressure.

Hope that makes sense

Cheers,
Eugene

Borderjumper · #7 12-25-2010, 07:01 AM

Makes perfect sense but now my question is.. Have you ever taken apart a seastar tank? Is it a floating bottom? I can't tell without taking the trim off.

imisky · #8 12-25-2010, 07:13 AM

never taken apart a seastar tank before, but most (80% i would say) of the tanks I've taken apart with trims are infact built with the side panels sitting on the bottom panel. So there is a high chance that the seastars were built the same way.

Borderjumper · #9 12-25-2010, 07:18 AM

Quote:

Originally Posted by imisky

never taken apart a seastar tank before, but most (80% i would say) of the tanks I've taken apart with trims are infact built with the side panels sitting on the bottom panel. So there is a high chance that the seastars were built the same way.

I'm getting confused lol so tanks with trim are floating bottoms and should not be on foam? Or, It sounds to me that if the sides sit ON the bottom glass that the bottom is not floating?

Doug · #10 12-25-2010, 05:40 PM

Shelley, although not much help now, sorry, but I agree with no foam under a framed tank. We had many threads on RC in regards to it. One builder even said it voids there warranty if foam is used under a frame.

Any tank thats custom made, with no frame, where the complete bottom sits on the foam is usually fine.