Silicone for Aquariums
It's just 100% silicone. I suppose any sealant would work that is 100% silicone. It just has to not have any additives.
looking into it a little deeper, silicone sealants use a variety of plasticisers, the most common being Acetic acid.
there are a few other, mis-conceptions, that go with needing "AQUARIUM SPECIFIC" silicone. lol
ACETIC ACID, will poison you fish, if you don't let it cure, before filling. which is not true. all that will happen is, the silicone will never go off (cure). and it makes it unnecessary to leave the tank, longer than the cure time. before you fill it. its also why you cant do repairs, with silicone, underwater.
make sure you put a good amount in corners and stress points. this is only true, to an extent. if you make it, too thick, it will lead to the silicone, NEVER, curing completely. cure times, stated by the maker, are based on the amount of time needed for a 1cm2 bead of silicone to cure. thing is though, if the bead is thicker than 1cm2, the silicone will never fully cure. trick is, to put the thinnest layer of silicone you can, but ensure it is continuous. allowing no voids and bubbles.