I made some DIY foam backgrounds for my tank. One is a rock wall and the other a (hopefully) rock sand waterfall.
I bought some ceramic tile to silicone to the bases to help weigh them down (also using strong water safe magnets) but to do that I will have to cut out some of the foam, after it has already been painted, to make a place to glue in the tile flush.
Can anyone tell me if the foam (hobby foam from Lowes) will break down in the tank and cause issues? Is it safe to just put it in there without being 100% full sealed? I figure the silicone will also seal it up but I KNOW there will be places where it will just be foam against the water.