Why Does Algae Grow In My Pool?

Algae – Those tiny plants that range in color from green to brown to yellow to red…and the scourge of them all…black. Black Algae? Oh, yes. Except that they are really a blue-green color.

Algae are unsightly and a nuisance. Although they are not themselves pathogenic, they can nevertheless be dangerous. Algae are often covered with a slime layer which is slippery. and they can be a hiding place for bacteria.

Under a microscope algae resemble a tiny apartment complex. Like most plants they flourish by consuming nutrients in the water (things like perspiration, urine and other swimmer waste). They also need plenty of sunlight to carry out photosynthesis. Most types of algae won’t grow in the dark…which is why you usually find algae growing on the sunny side of the pool.

Some forms of algae actually can ingest calcium, which they can find in the water or in the walls of a plastered pool.

And then there are the kinds that float in the water. And kinds that cling to the pool’[s interior surface.

Of the more than 21,000 types of algae, only about 40 to 50 inhabit swimming pools.

No, we don’t kill all the algae. Or bacteria either. We merely control them with chlorine, for one. And with algaecides. Algae spores are just waiting for a chance to get with the program. Let your guard down, and watch them grow. Rain, dust, wind and not telling what else bring algae spores into the pool water 24 hours a day. You’ve got to be ready for them.