WE INSTALL POOL PLASTER MOSTLY IN REGULAR SWIMMING POOLS. A CUSTOMER OF OURS IS BUILDING A SALTWATER SWIM POOL THAT WILL BE FILLED WITH OCEAN WATER LOCATED IN MIAMI, FL. WE ARE AWARE OF AND PLAN TO USE A SILICA-FUME TYPE POZZOLON ADDITIVE THAT WILL DENSIFY OUR MATERIAL AND MAKE IT LESS...