Foam under a SeaStar tank?

[Borderjumper]

Originally Posted by Doug

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.

Thanks Doug.. I'm just trying to come to a conclusion as to why this tank failed.. I'm prolly going to have a new one built and I don't want this happening again.

I think there is some confusion as to what foam I used. It's not spongy carpet underlay type foam. I have other tanks sitting on very thin open cell black actual foam.. Spongy foam.. I think that's ok as it can totally compress.
This pink building insulation sheet foam is over 1/2 thick and will not hardly compress even if you stand on it. IMO it's so rigid that once the tank edge settles IN to the foam the whole middle of the tank has an upward force pushing against it.

I won't use it again,, I'm going back to the thin open cell spongy foam, if any foam at all.