[Guest]

I used the "great stuff" expanding foam as a background. I waited over 24 hours. The foam was hard and I decided to cover it with black caulk and cocofiber.. To my surpirse and terror a couple days later the foam is shrinking away from the sides of the glass. Has anyone else have this experience, if so how did you remedy it?
:shock:

 

[Angieownsbatman]

Lol the exact same thing happened to me. At first I considered taking out the Great Stuff and going with a more traditional design, but it was hanging on to my perfect piece of drift wood that i was not about to get rid of. I just stuffed the cracks full of substrate, making sure there was absolutely no space for froggies to get in. I haven't quite figured out how to seal up the top yet. Perhaps more Great Stuff? If I come up with anything that works, I'll let you know.

 

[Dunner97074]

I haven't had the unlucky experience of shrinkage (except after the pool) :shock: But I got the pink insulating foam and great stuff'd on to that. It doubles as insulating the tank and giving the great foam something to bind to instead of the glass.
Mike

 

[Guest]

You get the shrinkage from applying too much expanding foam at once. It should really be done in thin layers and allowed to expand and cure. That way, you can come back with additional layers and cover and fill in any areas that have shrunk. I did the same, but filled in the areas that had pulled away from the glass.

 

[Guest]

OK

Alright. I covered up all the holes with the sealant and coco fiber. Aweek later I put a waterfall in it and covered the lid. It looks like the foam expanded and made new areas I will now have to cover up?

I don't know why I am having such a problem with this.

 

[Guest]

Sounds like you need to lay thin layers of foam down, one at a time, and let them fully expand for a couple days

 

[Guest]

The odd thing is that it has been a month since I put foam in there. Will it always expand and contract? Or does it take a full month to settle?

 

[Guest]

Can't tell, usually the foam takes 24 to cure.