Minerals from water can leave deposits on your gunite swimming pool and build up rather quickly. Calcium is the most common mineral deposited on swimming pool walls, leaving thick white spots on the gunite surface. Because of the characteristics of a gunite pool, you need specific cleaning tools and careful application to protect the integrity of the pool floor and walls.
Keep the calcium harness level in your pool under 350 PPM to reduce calcium deposits.
Balance your pH levels in the pool between 7.4 and 7.8. At these levels, it will take a very long time for mineral deposits to build up.
Lower the water level in your pool to expose the calcium spots for removal.
Mix two parts muriatic acid with one part water in a plastic bucket.
Dampen a clean sponge in the acid solution and rub it onto the calcium deposit.
Scrub the spots with a polyblend fiber handheld brush.
Rub the existing calcium spots with a wet pumice stone to release the mineral deposits.