Algae and water temp?

[PhillipH]

Is there a general consensus on a target water temp to shoot for when closing down the pool in the fall? I assume that the longer you wait and the cooler the water gets, the less likely you are to develop algae.

My local pool store is recommending Arctic Blue winter algaecide as the product to use when closing down the pool. However, it contains copper, and I've read that too much copper can cause problems (staining?). So, I'm worried about using a copper-based product (plaster/gunite pool). I've seen people at TFP talk about PolyQuat 60, and I don't think it is copper-based. I'm wondering if there is a difference in effectiveness and why I should use one over the other. I think my local pool store also has PolyQuat 60, but it's a different brand.

This will be my first year to close down the pool.

Thanks,
Phillip

 

[MikeInTN]

Phillip,
There's an article in Pool School that addresses all of your questions. Just click on the "Pool School" button to the above right, and scroll down to "Pool Equipment".

If you have problems finding the article, post back and I'll be glad to help you.

Mike

 

[PhillipH]

Thanks. I have read several Pool School articles, but I hadn't seen that one and I keep forgetting to check it first.

I didn't see anything about Polyquat vs the normal copper-based algaecides? Can someone compare/contrast so I know why to pick one over the other? It seems like most on this forum favor Polyquat.

Thanks!

 

[chem geek]

Copper-based algaecides can lead to staining, though they are an algaecide that will persist through the winter. PolyQuat will not stain nor have any other negative side effects, but it most likely will not last through the winter; nevertheless, if you are going to be using anything other than chlorine, it is PolyQuat that is recommended on this forum. The best approach is to wait and close when the water is as cold as possible, especially below 50F is helpful. If you open for spring before the water gets above 50F, then that is also preferable. Though algae can grow even in freezing water, it grows far more slowly.

 

[MikeInTN]

In the FWIW column, I didn't use PQ60 at all last year. Waited until the water cooled down, brought my FC up to shock or a little above shock, and covered 'er up. Opened to a crystal clear pool this spring.