I am very anxious about my cya leve. I live in sc and it is usually very hot. The sun is on my pool all day,no shade until late in the evening. My question is should my cya level be at 50 or should I shoot for 30 or 40. Most folk say to shoot for 40,but I have noticed spots of algae over time. I use tf100 test kit. I have kept my cl at the target suggested by pool calculator for cya at 40. I use 6% bleach,WalMart brand. My last checks cl 5,ph7.6,ch50,ta70,cc0,cya35-40. I really do appreciate the help I always receive from all of you. God speed.