I was just wondering if all silicone is safe for aquarium use or if u need a certain kind. I need to fill in some ornaments really soon before I can put my new froggies in their new home, my dad has silicone but I just wanna be sure it isnt gonna harm the fishies/froggies.

NO...not all silicone are aquarium safe. you could get aquarium safe silicone from home depot or lowes. the only non aquarium application silicone thats safe for fish is the GE silicone 1 for windows. make sure to get them WITHOUT the bio-seal

I get mine from the LFS, that's aquarium safe.

My LFS owner told me today that it is water tight after a cure period of 48 hours. But since I am using it to replace/repair a center brace on my tank, he recommends a 14 day cure period, since it's going to be used to keep the integrity of the tank intact.

I am not too happy about that. I was hoping I could refill my tank in a few days time.

is aquarium sealant ok for filling ornaments?

Aquarium sealant is generally the same thing as silicone, with a higher price tag (at least in my area). GE Silicone I is great. DO NOT get Silicone II (it will say that it is mold and mildew resistant), as this contains chemicals that kill mold and mildew, and will kill your fish. If you want to fill the ornaments so that you don't create stagnant water pocketys, you could drill a few small inconspicuous holes in the ornament...