Q: I got home from work last night and couldn’t wait to get into my pool to soak away the day, but when I got to the backyard, the pool water was green—not light green, either, but dark. I didn’t even ...

A swimming pool is a highly sought-after amenity in a household or community. For those who live in coastal areas, a swim by the sea does the trick every now and then, but for people who live far from ...