I have followed this site extremely closely and have done alot of what I have seen recommended. Here is my problem: We have an in ground L-shaped pool approx 35,000 - 40,000 gal of water. it is crystal clear but it will not hold chlorine. it gets full sun all the time, but I tried to shock it last night with bleach and woke up this morning and tested and theres nothing left. I used the test strips and now I know I need a FAS DPD Test kit in order to get more accurat results. I dont know how high the FC went up too because it only goes to 10. I put 1274 oz of bleach in my pool! and now there is nothing in there. The[quote] CYA is staing right around 80-100. We have a Chlorinator and in it there are Trichlor tablets. I know they add CYA, but the CYA is stabilized at those numbers pretty well. Howmuch freakin bleach do I need to add to get it to the shcok level that is required for the CYA number. I look at the chart and see 39, but I dont know it unless I get a kit. I did the pool calculator and it said for 40,000 add 223 oz. Well thats wrong. please help me! We have spent over $400 on chemicals already.