I just want to verify that when doing the CYA test that your looking for the black dot to entirely disappear.
I added 3lbs of stablizer to my pool(15k gallons)and my CYA reading is still at 0(or below 30ppm). I had also been using trichlor tabs up until 3 days ago. So far my TC level has remained well above 12ppm and I havent added any bleach for the last 3 days trying to get it down to 3ppm.
Thanks
John