First of all a brief history-
We've had the pool for about 8 years now. Seems like every year I have some kind of algae issue. I think part of my problem is all the trees around me... I only get full sun from about 10am to 3:30 pm. I found TFP late last year and after some thought, decided to try the liquid chlorine method this year. Actually, want to use up my remaining 3 in 1 tabs, while monitoring CYA. I figure when it starts creeping up, I'll make the switch.
I just installed a new liner, filled pool and water is nearly balanced (see below). Like last year, I am already starting to see a black scum ring developing in the skimmer box. No one has been in the water yet, so I don't think lotions, etc. are a concern.
I installed new sand in my filter last year, by the way.
Can anyone tell me why this is happening and how to correct it?
FC-12.5 We've had a bit of rain so I did add some liquid bleach (obviously too much)...
You can start to see it in this pic: