I always used Pondpro2000 for sealing inground pools, here are some advantages of using pondpro2000;
Water resistance: PondPro2000 is superior to epoxies, urethanes, acrylics, polyesters and alkyds at equal film thicknesses and is not affected by continuous immersion.
UV resistance: PondPro2000 is equal or better than acrylics, polyesters or urethanes and much better than alkyds and epoxies.
Temperature tolerance: PondPro2000 is better than all other coating polymers except silicones. EPDM can withstand live steam as well as cryogenic temperatures.
Flexibility: PondPro2000 is better than all other coating polymers except silicones. EPDM can withstand live steam as well as cryogenic temperatures.
Chemical Resistance: PondPro2000 has very good resistance to strong alkali's, concentrated salt solutions, many acids, and alcohols.
Surface tolerance: PondPro2000 will not bond to a surface that is damp with moisture. PondPro2000 also can be applied directly to metal surfaces that have tightly adhering corrosion without a primer.