Repair all cracks, pits and holes (if necessary) before preparing the surface. For details about pool and deck repair, click on the Pool and Deck Repair link back on the product page.
The most important aspect of pool painting is surface preparation. Paint will not adhere to the slightest oily residue, such as suntan lotion, body oils, hairspray, algae or anything else that comes between the pool surface and the paint. The best method for preparing your pool is described in the following steps.
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
Mix 8 ounces of tri-sodium phosphate to each gallon of warm water. One gallon of this solution will wash approximately 200 square feet.
Scrub the surface vigorously with this solution. Rinse off the residue with clear water immediately after scrubbing. Be careful not to allow the pool washing solution to dry on the surface -- work in small areas.
Always scrub the pool walls first, then do the floor last.
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.
Acid etching opens millions of tiny pores, which allow the subsequent paint coating to penetrate the surface, thus creating a secure cohesive bond.
Even on previously painted pools, we strongly recommend an acid etching.
NOTE: To prevent eye injury, NEVER pour water into acid. Always pour acid into water and wear protective eyewear.
Making the Acid
Mix in a plastic bucket a 10 percent solution of muriatic acid in water. (do not mix solution in a galvanized container) Most muriatic acid is packaged at 20% or 30% strength. One gallon of 30% muriatic acid mixed with 2 gallons of water will yield three gallons of 10%solution. Likewise, one gallon of 20% muriatic acid mixed with one gallon of water will provide two gallons of 10% solution.
One gallon of 10% solution is sufficient for etching 100 square feet of pool surface.
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.