Helpful Hints: Gearing Up for Spring: Pool Surface Prep
Washing your concrete pool is important to remove any existing oil residue. The best washing solution is tri-sodium phosphate (TSP) mixed with warm water. NEVER use a soap-type detergent.
How to Wash Your Pool
Mix eight ounces (0.23 liters) of pool washing compound or tri-sodium phosphate to each gallon (3.78 liters) of warm water. One gallon of this solution will wash approximately 200 square feet (18.5 m2). Dip a long handled brush in this solution and firmly scrub the pool surface in approximately 10 foot sections. Rinse off the residue with clear water immediately after scrubbing. Be careful not to allow the pool washing solution to dry on the surface. Always scrub the walls first and the floor last. The next step is acid etching.
Acid Etching - for Bare Concrete and Plaster
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 coated pool. Acid washing opens millions of tiny pores which allow the subsequent coating to penetrate, thus creating a secure cohesive bond. Even on previously coated pools, we heartily recommend an acid wash.
NOTE: To prevent eye injury, NEVER pour water into acid. ALWAYS pour acid into water and wear protective eyewear.
Mixing the Acid
Mix in a ten percent solution of muriatic acid in water in a plastic bucket. Most muriatic acid is packaged at 20% or 30% strength. One gallon (3.78 liters) of 30% muriatic acid mixed with two gallons (7.5 liters) of water will yield three gallons (11.3 liters) of ten percent solution. Likewise, one gallon of 20% muriatic acid mixed with one gallon of water will yield two gallons of ten percent solution. One gallon of the ten percent solution is sufficient for etching 100 square feet (9.25 m2) 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 bubbling ceases, rinse the solution off with clear 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. It is of utmost importance that you wash the pool again after etching. The tri-sodium phosphate in the pool washing solution will neutralize all traces of acid left on the surface after etching.
The suggestions listed here are based on experience in the industry and they do not reflect recommendations for any specific project.
Instructions Courtesy of: 