Why do Cape Coral pools turn green so quickly?
Warm water is the main reason. Pools in southwest Florida stay warm for most of the year, and algae grows fast in warm water with plenty of sunlight. Missing a week or two in summer can be enough to change the color of a pool.
The rainy season adds to the problem. From roughly June through September, afternoon storms drop rain into the pool, dilute the chlorine and wash in dust, pollen and leaf litter. Heavy rain can also push the pH off target.
Debris around the lanai
A screened enclosure keeps out most leaves and many insects, but not fine dust, pollen or what drifts in from nearby palms and trees. Canal-front yards can see more bugs and airborne mess. A pool without a cage needs more skimming and brushing than a caged one.

