Green Algae

[duraleigh]

Hi, Lynn,

I assume from "Gemstone" that you do not have a vinyl liner...correct?

[lynn2_cal]

correct, it a pebble finish

[duraleigh]

Your CYA is very high. I would take the Cl ppm up to 30+ to insure you have reached breakpoint. That will most likely clear the algae from your pool. Be persistent with the high Cl until your water shows no trace of algae.

FAC(FC) is free chlorine that's good for your pool. CC is combined chloramines that don't do any good but are still there. When you test for TAC (TC), you get the total of FC and CC.

By shocking your pool, (30+) you will get rid of the CC's and your FC and TC results will be the same number. Your pool will clear up as well.

I'm assuming you don't have an SWG.

Your high phosphates may be contributing to your propensity to grow algae...I have no experience and cannot comment on that other than to say high Cl levels are the best preventative.

Lastly, consider draining 1/2 your pool...maybe twice. That's not too much water and it may give you a fresh start on CYA levels and reduce the phosphates.

[lynn2_cal]

Thanks,

yes I do have a SWG. Should I wait to drain 1/2 as a last resort? Will it hurt anything with the chlorine up at 25 to turn off the pump if I drain?

[duraleigh]

Thanks,

yes I do have a SWG. Should I wait to drain 1/2 as a last resort? Will it hurt anything with the chlorine up at 25 to turn off the pump if I drain?

Hi, Lynn, Yeah, that changes somes things...I should've asked you that first. Yes, drain as a last resort.

Leave your CYA up there at 100...it's alittle high for SWG, but it'll dilute with rain and refill.

Still shock the pool as in the earlier post. That'll clear your water, get rid of the CC's and not put a strain on your SWG by asking it to do it. (They're not really good at shocking.....particualrly those high levels.)

Still can't comment on the phosphates...I have no experience

[lynn2_cal]

Thanks again duraleigh,

I tested again and chlorine was down to 18, added 1 1/2 gallons bleach per bleach calc. to get up to 30.

I'm not worried about the phosphates now either. They were way down after adding the PhosFree.

[lynn2_cal]

Other questions, do I need to keep the chlorine up around 25-30 for a week? I'm not seeing any algae this morning, it's been 2 days now with pump running 24/7.

Again, how do you know algae is dead?

Can I run my navigator in water with that high of chlorine?