When you seal your tank make sure you give it 7-10 days before you run water.. wash it well and then give it a few days running before you put fish in. Silicone, even aquarium safe, can be toxic to fish if not cured.
Life should not be a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside in a cloud of smoke, thoroughly used up, totally worn out, and loudly proclaiming "Wow! - Hunter S Thompson