Turn the pump directing water through the fountain off, and then remove the pump mechanism with screwdriver and wrench, leaving only the fiberglass fountain body behind.
Clean any dirt or debris from the fountain using a cleanser created from 1 cup of bleach mixed in with 1 gallon of water in a 2-gallon bucket. Use a sponge and a brass bristled brush to clean all of the nooks and crannies of the fountain. The bristles of a brass brush are softer than a steel wire brush and will not scratch the fountain surface.
Rinse the cleanser from the fiberglass and allow the fountain to dry completely for about 3 hours.
Apply an epoxy primer to the fountain in two thin layers to build up the primer coat. Use a paintbrush, working from the top of the fountain to the bottom to apply the primer, and make sure that you've covered the molded color of the fiberglass is completely in primer color. Give the primer two hours drying time before continuing.
Apply your topcoat of epoxy pool paint color over the primer coat, working as you did with the primer from top to bottom. Use multiple thin layers, allowing each layer to dry for about an hour until you cover the primer layer. Allow the last layer seven days of curing time before reconnecting the pumping mechanism and restarting the fountain.