Harmful Effects of Humidity


askthepoolguy-banner2How to protect your pool

With heat often comes humidity. While you may feel the effects of those warm humid days, it’s important to remember your pool also is affected by humidity. Maintaining your pool during the hot summer months and during those humid days can be complicated, so here are a few tips for keeping your pool healthy and sparkly throughout the season and into next summer.

What’s Growing in My Pool?

As hot weather continues, pool owners may go outside one morning to find their pool covered with little red, black, or green algae blooms. Treating your pool quickly is essential. Sudden algae blooms can cause greater damage to the pool and to the pool equipment than you would think.

Algae blooms in the heat and multiples rapidly on warm, sunny days. In addition to clogging up sanitation pathways in the water, algae also clogs up the pores in a filter, decreasing filter effectiveness and requiring more backwashing or medium replacement. Chlorine is the best defense against algae- particularly at the moment, with the continuing hot weather. And if you have a salt pool, you can use the ‘super chlorinate’ button on your salt chlorinator to fix the problem.

Keeping in Balance

One of the best ways you can keep your pool protected from the effects of humidity and prevent algae blooms is by maintaining a proper pH level in your pool. Either a high or low reading can cause problems.

The hotter the weather gets, the more the pool is used and, as a result, more chlorine is required to keep it sanitized. Pools aren’t cooling down overnight, so the chlorine demand remains high.

High humidity makes maintaining the chlorine levels in your pool even more difficult, thus affecting the pH balance. Here are some signs your pool may have a higher pH level than normal:

  • scaling forming on the surface of the pool
  • scaling on the salt chlorinator
  • low pH levels may hurt the eyes of the swimmers

Adding an acid or an alkaline treatment to your pool will help ensure the pH levels.


Another factor to be aware of in the hot, humid days of the summer is the level of phosphates in the water. You may wonder, how do phosphates even enter my pool water? They mainly enter through bird or bad droppings, swimsuits, some clothing that is washed with detergent containing phosphates, and water washed off your roof. Phosphates are bad for your pool because they can act as feel for algae blooms, helping them grow and thrive in your pool water more quickly.

Be sure to test your water during hot and humid months. Proper chemical application and keeping them in balance will help you keep you pool clear and ready to swim.