Ascorbic Acid

[beechjetdriver]

I'm going to do an ascorbic acid treatment this weekend. My FC will be around 7 (CYA 50) by Friday (I would lower FC now, but I'm going out of town until friday). I know I want my FC to be close to 0 before adding the ascorbic acid. My question is should I wait until my FC is 0 to add the polyquat 60, or can I do that while FC is at 7, then wait for it to fall to 0? Thanks for your help.

Current test results:
FC 7
PH 7.6
TA 110
CH 170
CYA 50
Temp 74

 

[JamesW]

You could do it at FC = 7 ppm, but you could wait until the FC falls to 7.5 % of the cyanuric acid (3.75 ppm).

You could also use a little extra ascorbic acid to drop the chlorine to zero so that you don't have to wait for it to fall to zero. That will help reduce the amount of time that the chlorine is less than 7.5 % of the cyanuric acid

For your 17,500 gallon pool, 6 ounces of ascorbic acid will neutralize 1 ppm of FC.

 

[beechjetdriver]

Thanks for the quick reply!