GE Silicone 1..
 

Okay, I'm reading that it's safe browsing through the forums. But one post said "just don't get the kitchen and bath stuff."
Well that's what I bought, but it says 100% silicone on it. (I picked it because it said waterproof. :P)

It says "not for use below the waterline, where FDA compliance is necessary, or in aquariums."
The aquariums part is fine apparently, but not for use below the waterline? What?

Should I exchange it for the doors and windows type?

ABSOLUTELY DO NOT USE IT.

The kitchen and bath stuff has fungicide and mildew resistor will seriously harm your tank.

Windows and doors has been confirmed as safe.

Leave it an extra 2-3 days to cure before using below the waterline to make sure it is fully cured!

Thank you Taz!
This silicone stuff is ridiculous. I was staring at them for like half an hour and still picked the wrong one.

Personally I believe that GE 100% clear silicone II is also okay. Taz is correct-kitchen and bath type typically has a fungicide to resist mold and mildew, which makes it bad.

Agreed .

Thank you everyone! SO glad I asked!

Why not just buy the silicone marineland makes? Made for fish tanks.

I need A LOT of silicone- I'm making rock formations for my 90 gallon and resealing the tank as well.
I've looked for fish silicone, but only my LFS has it, they want $10 for a tube 1/4 of the size of the GE Silicone tubes... I can't imagine how many of those tiny tubes I'd go through.
:-)

I believe marineland sells bigger tubes on line. Check It out

Tons of people use the GE Silicone and it's fine.. (just not the type I bought)