Silicon

[bamboo]

Can I use common silicon to seal my tank? Or is there a certain one needed for fish tanks?
Thank you for your advice

[MSU Fan]

GE Type 1 Silicone Doors and Windows (with no added mildew/mold blockers) or DAP aquarium silicone are the only ones that are generally accepted.

Whatever you choose, do not get any silicone that specifically says "do not use in aquariums" or includes any form of mildew/mold preventative.

[rich311k]

All Glass markets a brand. Most pet shops have it. A little expensive but if you only need a little, you don't have to worry if it is safe or not.