Thank you. I've already closed the pool using the usual Poly60 algaecide and chlorine, but we bought this "Winter Pill" thing when we saw it in the pool place the other day. I want to add it also, as long as there's no known ill effects from using it.

I also add some liquid chlorine about 2 weeks or so before we open it and it has helped alot. We have a mesh safety cover and in the years past before we started adding the chlorine before opening we never knew what sort of green mess awaited us. It's been much getter adding some liquid chlorine about 2 weeks ahead of time.

Vickie

Quote Originally Posted by chem geek View Post
You would be better off spending the money on PolyQuat 60 algaecide and chlorine. The WinterPill appears to just be enzymes, and these will help speed up the breakdown of organics to prevent scum lines in the pool, but it won't kill bacteria or algae by itself. It still needs a strong disinfectant or oxidizer such as chlorine to do that or at least an algaecide to inhibit algae growth.

The easiest thing to do in the winter to keep the pool great upon spring opening is to add chlorine periodically during the winter, though far less frequently due to the colder water temperature. For closing, you can shock the pool with chlorine and then the next day add a strong "algae killer" dose of PolyQuat 60 algaecide and then close the pool. There are somewhat mixed results from doing this without any maintenance during the winter, but for most it works OK. Adding some chlorine just when there's a thaw in the spring will also help prevent an algae bloom.

Richard