Just finished a week and a half war with the dreaded black algae and am claiming victory. Just got a TF-100 kit yesterday and am now in the process of bring our pool into balance and beginning the BBB method. We have a 25,000 gal plaster pool with a DE filter. I will be taking the filter out this afternoon, degreasing it, and recharging it with DE.
My goal is to achieve a CYA level of 40 and keep the FC at about 6.6 to meet the CL/CYA Yel/Mustard algae min. and provide a .5ppm buffer. Presently I am at 20ppm CYA and 10.5ppm FC. My pH is reading 8. I had been running at very high CL levels - 40-50 ppm. It is hot here and I have a fountain so can take the FC down fairly quickly.
I have read that pH, TA, and Ch readings are inaccurate at high CL levels.
1) At what point (in FC test readings) can I "trust" my pH readings and make an informed trip to the Pool Calculator and adjust my pH ? At what point can I "trust" my TA readings ?
2) After I Pool Calculator calc the CYA needed and add the stabilizer, approx. how long does it take with a clean DE filter that won't need backwashing for awhile to test accuratley for CYA ? Should I add the stabilizer all at once or over time ?
3) Should I wait until after adjusting pH and FC and adding CYA to adjust for TA, if necc ?
4) I thought I read somewhere that with the TF-100 it was possible to test FC in .2ppm increments (instead of the .5ppm that the kit articulates) by altering the test procedure somehow. Am I crazy ?
It has been a long two weeks. I want to thank everyone in this forum for their help. I have learned a lot and am very grateful for the amount of knowledge, however small, I have picked up from this forum. While I have never been to prision, I do think I know how someone feels when they are about to be released.