Innotec sealant small tube
Superb product for repairing liners, sealing pipes repairing plastics gluing to concrete etc etc, 30 times stronger than silicone. Best sealant we have ever used, can even work underwater.
Innotec Adheseal has been used to build, repair and maintain aquariums, ponds and garden water furniture for many years. It is also completely non toxic even when curing to livestock including invertebrates and crustaceans.