Unhappy Rookie Mistake-Great Stuff Background failing!

[MarcNem]

It's been almost 4 weeks since I began construction on my 18" Exo cube. I used Great Stuff foam for the background (and sides), which I let cure for almost 2 weeks. Then I put a generous portion of silicone on the background and pressed in a coco fiber mixture. About 10 days later I planted it. I checked it one last time today, and I noticed that the background was beginning to separate from the glass, and there was a 1/4" space between the foam and glass. I have never had this happen before with a foam background.
I also normally seal all the way around the GS, to make sure there is a good seal to the glass, in case the GS shrinks. I did not have enough space between the black plastic rim of the tank and the top of the foam. So, it was bare, but visible.
I believe the problem was a combination of two things.
1) I used a very heavy piece of Malaysian driftwood. This wood is very dense. I did not support it in any way, except for the GS foam, and the weight of the wood pulled the foam away from the glass.
2) I did not seal the GS all the way around the glass with silicone. This would have helped support the weight of the wood, and keep the foam against the glass.
The goo news is the tank is not ruined. But I am going to have to figure out how to support the wood, and stuff some moss between the crack, so the frogs won't squeeze back there.

I guess the moral of the story/lesson learned when using GS for a background with Malaysian drift wood, is to make sure you put enough GS to support the very heavy wood and make sure you silicone all the way around the GS, making sure there is a good seal to the glass.

The part that really sux, is I was planning to put my new 1.2 Cayo de Agua pumilio in there. Guess they gotta wait a lil longer.

Below are a few pics of the damage:









If this helps one person, then it was worth posting.
Thanks

[kyryah]

Can you run a bead of silicone in the crack to seal it, and press some dry moss into it while it is still tacky?

Kristina

[RecycledAgain]

I'm curious. is it getting worse ? or is it stable. Maybe prop it up with more wood and pack the gap with sphagnum moss.

[MarcNem]

I planned on stuffing moss in the gap. But, I wonder if gravity will take its toll over time.

[kyryah]

That is why I am wondering if you can stuff some silicone in there before you stuff the moss in there. It might help hold things together.

Kristina

[MarcNem]

I will do that. I will prop the wood up, then goob the silicone in there. And add a coat of coco fiber mix.

This is hindering progress, seriously! I have a group of Cayo de Agua pumilio waiting. They're trying to breed in the 10 gal holding tank.

[kyryah]

Maybe even gob some in before you press the background back into place, and then use something that will hold it there while it cures, and silicone the edge. It will hopefully act as a glue to keep it where it belongs.

I am sorry, I have dealt with tough hold backs too and it stinks.

Kristina

[MTviver]

wow, sorry to hear about it. I think as long as it is dry, the silicone will hold. just get a whole bunch back there then use clamps or something to hold it while it cures. good luck.

[RecycledAgain]

The tank is planted, ='s wet in my mind. If you pack in the silicone I am afraid you will have 2 problems;tough call. If the tank has time to cure empty and open, go for the silicone. Other wise Prop up the wood and pack with moss.

Dan

[froggsong]

I'm sure there are other glues or adhesives you can use... You could probably use some two way tape to hold it in place and pack moss around it to seal any remaining gap. If you try a glue of some sort, just test it on some GS somewhere to make sure it won't melt it.

Of course, you could always spray a little more GS in the crack, if you have a can that you can use for something else. They should make tiny cans of GS for small applications.