I ordered this product, because I could get two for less $, thinking it would work as the solar fish do. Instead, this is a ball that goes in your skimmer basket, is supposed to empty in 4-6 hours and last for a month. I didn't realize the ball didn't empty as it was supposed to and when I pulled the ball out, this white stuff oozed out of it. Also, I can see the skim of it on top of the pool. I hope it only lasts for a month! The solar fish stays in the pool and I never saw a skim on my pool. I won't be using the second one and will probably sell it at a yard sale for less than I paid for it, just to get rid if it. My pool is warmer, though.

Sounded too good to be true, and it was! It didn't warm our small pool (16 feet by 20 feet)