thanks again!
I am going through cl like it is going out of style!
after adding a total of 18 gallons of 12.5 I still can't get a reading above 1.5 fc with the test kit.
I hope I am reading it right, I will certainly run to wall mart in the a.m to fill my pick up full of bleach.
I know my baq oxidizer level was high when I started, so I am sure that is the culprit.
The water turns deep brown right after I add the cl, than fades to light green.
I have back washed several times and will keep testing every hour, adding cl until I go to bed.
Hope this is the proper procedure.