jetskiron

Thanks much. You explain it very clearly. Then is there a way to reduce the CYA without draining the pool and refilling?

thanks for the great information. Well, I'm more comfortable knowing that staining and green hair is the worst. I'm glad it won't do something worse like damage fittings, etc. I see that I need to get off the copper use and read the Pool School link. I posted more details about my situation on the post Chem Geek referred to (I can't find the post ID), about copper ammonium complex.

Thanks so much for your help. So should I switch from the 3" Leslies chlorine tablets to a liquid chlorine in the gallon jugs? My pool is 20 years old and until a few years ago, I always had to add muriatic acid to balance the ph. But then I had to start adding the soda ash instead if acid. I also went from 1 hopper of chlorine when the pool was new, to 3 hoppers and could never get the pool completely algae free. It still had the green algae in the scratches in the plaster (from dog clawing I think) and the Kreepy Krauley had algae I could never get off. I was brushing the pool every day about 20 minutes. Then I tried a quart (half the recommended amount for my pool size) of the HTH Algae Free (Copper Sulphate) from Wallmart and within a week, there was not a trace of green algae anywhere. The pool was cleaner than it had been in years. And it stayed that way for a couple months, and with only 1 chlorine tablet hopper. Then in the space of a week, the algae came back like crazy. I think I failed to keep the hopper full and the copper was about at its end anyway? So this is why I wanted to continue the copper treatment. The label on the bottle also said to continue with 16 oz/10,000 gallons of water every 3 months. I have not had the staining, and had been real happy with the algae being gone. But now you say don't use the copper algaecide. So I'm lost now. I will follow the Pool School link you provided. Thanks again

Some pool experts say only use chlorine to treat a green algae problem. What are the disadvantages of using copper? Copper not only cleared up my algae problems, but I went from 3 chlorine hoppers to 1 in a 36K gallon pool in central Cal.

Can I use copper ammonium complex as an algaecide in my inground swimming pool in place of copper sulphate pentahydrate? And if so, would I use it in the same concentration?