GE silicone

You might try calling the toll-free number on the tube and asking them.
 
It may be partly a liability thing, but I read on a nother forum that they say "not for aquarium use" because its the same stuff they repackage FOR aquarium use, and the markup is so much higher that they don't want to cannibalize their own sales. Not sure how true it is, but I've used Silicone I for many projects without ill results.
 
GE Silicone I has been used plenty of times, including myself. You must make sure it is clear and has no anti mold/fungus inhibitors as mentioned before. There has been a discussion about this in the past and the reps at GE as someone previously stated do not want to take liability.
 
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