Which color solar blanket works the best for heating up a pool during the day? I know that any cover will help reduce heat loss at night, but I'm interested in daytime performance.

One site claims that Blue top with a silver reflective bottom works better, but is that just marketing hype. It seems like a black bottom would absorb alot of heat and transfer would be made to the cooler water below.

Are there any proven results with these various cover options.

1) Blue/Blue

2) Blue/Silver

3) Blue/Black

4) Clear