I have been having a problem for past 3-4 weeks with dark green algae buildup on very shallow sun shelf. Water has remained clear. Pool is in full sunlight all day. I have read Pool School, but can't say I understood it all (yes, I'm feeling kind of stupid). I have a new TF-100 Test Kit. Just completed all tests and readings are as follows:
CYA= too low to register (dot stayed visible)
I realize I need to shock the pool. (BTW, I've been adding a bleach bottle or two a day for past week trying to keep chlorine level up to normal until this test kit arrived today. I did not add any bleach today so chlorine has again fallen).
I am feeling confused as to what my target shock level should be with no CYA. Or should I add CYA and get that level to 70-80 before beginning shock process? It says it can take up to a week for CYA to register on the test. I would like to get this under control ASAP, but I'm not clear as to how to begin (and also feeling like I really don't quite "get" it).
Any help is greatly appreciated.