Why does my pool get algae?

Unfortunately, algae spores are present in practically all forms of non-purified water -- including tap and source water. It takes literally millions of algae spores per fluid ounce before visible growth can be detected; so, it's entirely likely that even the most appealing swimming pool has non-visible levels of algae present at any given time.

When chlorine levels are consistently maintained at proper levels, most algae strains cannot thrive and bloom.

However, there are some strains that can be chlorine-resistant and still find their way into your pool (blown in like pollen, as an example).

Since all forms of algae need nourishment to grow and multiply, maintaining a regular shock routine and potentially using phosphate removal products can effectively help to avoid allowing those necessary nutrients to build up in the water over time.

Consult with your local and trusted pool professional for a preventative maintenance program that best suits your needs and budget.