Using your kitchen faucet to heat the pool

[Tredge]

The primary function of a solar cover is to prevent heat loss....the black matt Idea would help heat the pool in the day but do nothing to prevent heat loss.

I have a feeling you would gain more from a simple cover to prevent loss due to evaporation than you would adding a black matt to the bottom.

Good Idea though

[graciec]

Then why aren't solar covers black?

[JohnT]

Then why aren't solar covers black?

There are black covers. My guess is clear is better because then you are heating water, not the cover.