Advice needed please

Algae problems in swimming pool water.
Green (cloudy) water or slimy pool walls.
Black algae. Mustard algae. Pink or white pool mold.
chem geek
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Advice needed please

Postby chem geek » Thu 11 Jun, 2009 21:15

With a Cyanuric Acid (CYA) level of 69, the shock level of chlorine is around 25 ppm FC or so. It will take a lot longer to clear at 10 ppm FC so I'd suggesting raising the FC to the appropriate shock level. Turning from green to gray is normal. See this link for a pool getting cleared of algae using chlorine alone. Read Defeating Algae again and follow the advice there -- you simply are not using a high enough level of chlorine and have a lot to clear up in the pool. It didn't just take a few days to get in the bad shape that it's in and will take more than a few days to clear it.

Be aware that with Cal-Hypo, every 10 ppm FC that you add also increases the CH by 7 ppm. You never measured Calcium Hardness (CH), but your Total Hardness is low enough that CH is probably fine for using Cal-Hypo, at least for a while. You could also use chlorinating liquid at some point if the CH starts to get too high. You'll only know that if you get the proper test kit as I suggested.


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