I don't understand ...

[GolfTop]

Hardness level 550. And check that guestimate on CYA. It's actually zero.

[mwsmith2]

Weeeeeeel. With CYA of 0, you aren't going to hold shock levels in the sun for any length of time. Prolly want to get some stabilizer in there to take you to around 40 ppm cya. Then you can shock at 15 ppm and hold it there for a a while and see how that works out for you.

[GolfTop]

Working well so far. Stuff slowly clearing up but it apparently will take a steady hand for a while. I intend to keep at shock level until several days past time it disappears.

I'm considering shocking more often as a precaution, even without combined chlorine, to make sure that the stuff doesn't return.

In case this doesn't work, I'm prepared to rent a backhoe, fill it and make a nice tennis or basketball court.

[mbar]

Ha, Ha, then what will you do on the sweltering days after you play tennis? Keep the pool and put the tennis court next to it! Anyway, hope you added some cya - so you can hold onto the chlorine. Your calcium is high - you may want to drain and refill some of the water to bring it down (it's the only way to get rid of calcium) If you have no combined chlorine, then you don't need to shock - as long as you don't let your chlorine get low, the water mold should not come back.

[GolfTop]

It's not quite 40-love in the pool battle. More like 30-15. Still some of the unwanted stuff showing up, but it's diminishing. Sounds like the key is to be persistant with the shock level, brushing, backwashing.

Funny about the calcium. I used bleach all last summer. Not sure where the calcium is coming from. Maybe tap water is rich in it.

Thanks for the response.

[GolfTop]

Just a follow up for those who might be wondering if the advice on this problem worked.

For now, it has worked perfectly. Pool has been at shock level for about a week or so and no evidence of the mold is present.

I plan to keep brushing, shocking and backwashing through Sunday at least to ensure it's all killed.

Thanks for the help.