Brush the rock fountain with a brass bristle brush. Work your way from the top of the fountain to the bottom of the fountain. Remove all loose debris from the rocky surface.
Set a hairdryer to low heat, and remove any surface dust that has accumulated on the rock. Again, start at the top of the rock fountain and work your way to the bottom.
Spray a gray base primer onto the rock. Hold the spray bottle at least 18 inches from the rock surface. This will prevent the primer from accumulating in puddles on the surface. Allow the primer to dry completely before painting.
Apply the first coat of stone-colored spray paint to the rock fountain. Again, hold the bottle about 18 inches from the rock surface. Work from the top of the fountain to the bottom. Spray the paint evenly and not too thickly. Allow the paint to dry thoroughly. Apply a second coat of paint to the fountain to ensure full coverage. Allow the second coat to dry completely.
Carefully apply a clear acrylic spray over the painted rock fountain to seal the paint. Hold the spray can about 18 inches away from the surface. Spray the fountain with smooth, even strokes. Check that the coverage is complete and that the acrylic doesn’t pool on the surface. Allow the acrylic to dry thoroughly, and apply a second coat to the fountain’s surface.