Wait One to Two Weeks, Depending on Location
Some pool supply websites such as Inslx Pool Paints and Marine and Pool Paint Warehouse direct pool painters to allow the epoxy paint on outdoor swimming pools to dry for at least seven to eight days. For indoor pools, they recommend two weeks.
Others Recommend a Shorter Wait
Other experts, such as Pro Pool Supply, Specialty Pool Products and Pool Center, suggest that only ten days of cure time is required for indoor pools and that only a five-day wait time is necessary for outdoor pools unless rain occurs, in which case, only an extra day is added to total cure time.
Since filling an epoxy-painted pool with water prematurely can cause a host of problems with your paint job such as blushing and blistering, it's best to err on the side of caution and adhere to the longer wait times. For outdoor pools, wait a seven days at a minimum after painting before filling your pool.