mguzzy
Gold Supporter
Excellent tests results! On the CYA reading we round up to the next 10, so we are going to call it 90. As Marty said, we need to know what kind of pool you have. Do you have a inground, above ground, vinyl, plaster, or fiberglass pool? The type of pool has a bearing on the method of water exchange..i can see the shallow end of the pool but not deep end. I will not add clarifier but puzzled on how to improve clarity.
Based on above, do I need to partially drain to reduce CYA?
You will improve your clarity by your filter's regular filtration. Clarifiers will cause the suspended material to coagulate and drop out, but it creates a gummy mess in your filter, especially a sand filter. Its just a shortcut at a cost. .. You are going to want to get your CYA down to 30ish with a drain and refill/exchange then we are going to SLAM Process to kill the organics. While the pool is drain and refilling you probably should deep clean your sand filter if you have never done it. Here is some reference material from the TFP Wiki:
Draining - Further Reading

Sand Filter Use and Care - Further Reading
