That makes the most sense that the FC has gotten too low I should not have relied on the strip saying it was 30-50. I am going to dilute it now and try the CYA test to see what the results say.

I mostly use bleach but I travel for days at a time for work with nobody to add bleach for me so I do use Trichlor tablets from time to time. I know that continues to increase the CYA so I do try not to use them except only when necessary.

My CH was 70 with the k-2006. I am not using anything to add calcuim to the pool (its vinyl liner).