How to Lower PH in a Salt Water Fiberglass Swimming Pool

A backyard swimming pool can be fun for the entire family, but there is much responsibility to owning a pool. Fiberglass pools are one-piece, factory-made shells and finished with a gel similar to the finish on a boat or a slide. Unlike a cement pool, a fiberglass pool's chemical levels do not change and are easier to keep in balance. Even so, the chemical levels must be checked daily during the swimming season. Of all the levels, the pH is most important because it affects the effectiveness of the chlorine in the pool. Improper pH level can also cause eye irritation for swimmers.

Things You'll Need

  • Pool chemical test kit
  • pH Minus (sodium bicarbonate)
  • pH Plus (muriatic acid)
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Instructions

    • 1

      Check the pool's pH level by following the instructions that come with the test kit. pH stands for potential hydrogen and is the relative acidity or alkalinity of the water. The higher the pH number, the more alkaline the water is. The lower the pH number, the more acidic the water is. A pool should have a pH level between 7.2 to 7.4 to be in balance. This number is important because tears in the human eye are a pH of 7.0 and if the pH in the water is too low or too high, swimming in the water could cause eye irritation.

    • 2

      Add pH Minus (sodium bicarbonate) if the pH is too high. Add the chemical according to the instructions on the label. Add pH Plus (muriatic acid) if the pH is too low. Wear protective gear as instructed by the chemicals' manufacturers. Add the chemicals in the amounts recommended. Allow at least 8 hours for the chemicals in the pool to stabilize.

    • 3

      Check the pH level in the pool again. If the level is still too high or low, add more of the proper chemical depending on the reading. Follow the directions on the label for the chemical being added.