In the heat of the summer swimming pools can get very warm. Nothing worse than expecting a COOL DIP in the swimming pool, but you jump into a hot bath. This method of COOLING a swimming pool works really well. You can make it for about $10 with parts from big box store. Run this system at night and in 2-3 days your pool temp will drop as much as 10 degrees.
Not only will it cool the pool, but this also acts like a pool fountain that the kids will love.