I'm new here. I have just begun a trial run of the CYA reducer.
Small 10K gallon in-ground pool in Northern California. Have been using a pool store for years to test my water and obtain chemicals to maintain my own pool. They have always recommended the Trichlor 3" hockey pucks which I have been using for years, but I have noticed an ever increasing required FC level to avoid algae. They tested my water recently and reported a CYA level of 150. I was suspicious that their test may have maxed out. I had been running a FC level of 10% of the CYA level in the past, but during the past year, I've had to run 20+ ppm FC to avoid a swamp. I am now doing my own testing using both a Taylor K-2006 kit and test strips. Multiple tests at different dilution levels showed my CYA to be 350 ppm (not 150 as the pool store printout said). So much for the pool store wisdom of using Trichlor hockey pucks (and testing accuracy).
I can't drain and re-fill my pool because of the drought. I decided to try the new Bio-Active CYA reducer.
I have reduced the FC level to 2 ppm - verified with 2 different kits and test strips. My PH is 7.4 - verified with multiple tests. Yesterday I dumped the contents of the CYA reducer pouch into my skimmer. I am running the pump/filter >8 hours per day. I intend to make multiple measurements of the CYA level every other day for the next week or so. Hopefully the CYA will come down to <100 ppm before the pool turns green! I'll post my results here. I'll be using bleach instead of trichlor from now on (after my CYA level comes down). Wish me luck!