Wear protective hand gloves.
In Surface Preparation
STEP 1 -- POOL WASHING The best pool washing solution is tri-sodium phosphate mixed with warm water. NEVER use a soap-type detergent. Soap products leave a film on the surface which will result in poor paint adhesion.
How to wash your pool
STEP 2 -- ACID ETCHING Acid etching is required on bare masonry surfaces like concrete or plaster. It is also effective for removing chalky residue and hard mineral deposits on a previously painted pool.
NOTE: To prevent eye injury, NEVER pour water into acid. Always pour acid into water and wear protective eyewear.
Making the Acid
The Etching Procedure
Liberally brush the acid solution on the surface. The acid will bubble on the surface when applied. As soon as this effervescence ceases, rinse the solution off with clean water. The surface should feel like fine sandpaper when properly etched. Splash a small amount of water on the surface to see if it is sufficiently etched. If the water soaks in fairly quickly, the surface is properly etched. If the water stands on the surface, another etching will be required or switch to a stronger acid solution before continuing with the rest of the pool.
STEP 3 -- WASH THE SURFACE AGAIN
We highly recommend repeating STEP 1: Wash the surface again with the tri-sodium phosphate solution to neutralize any remaining acid on the surface.
Do not acid etch fiberglass pools! To prepare a fiberglass pool for painting, sand the surface in straight lines using coarse sandpaper. This sanding will create a mechanical bond for the epoxy paint. Do not use an orbital sander.
Once the fiberglass has been properly sanded, perform the pool washing procedure described above. Allow the surface to dry and you are ready to paint.