SpaCare Leak Sealer 500MLLeak Sealer is a concentrated formulation to seal minor leaks in spas and hot tubs. It can be used for leaks in either the shell and or internal plumbing system. APPLICATION 1. Remove all cartridge filters, or for sand filters select the BYPASS option (if applicable) prior to dosing the product. 2. With the pump running add the required dose of Leak Seal slowly through the skimmer or in front of any other suction intake. 3 Leak Sealer is very heavy