Originally Posted by Elpez
Be aware and read the back all GE silicone I have seen say in the back not to be used under water or aquariums.
They put this on the tube as a disclaimer to avoid lawsuits if the silicone fails. GE silicone is what most people use just be sure it's 100% silicone and it is not the mold inhibitor stuff. I believe the stuff you need is called windows and doors.