Earlier this month we left for vacation for a week. I had my father in law come by and skim the pool every day, but I didn’t show him how to use the robot. When I left the FC was 8 and my CYA was 60. I added a pound of Cal-Hypo as I was heading out the door and that should have brought the FC up to around 12. When we got back, I had leaves in the bottom of pool (obviously) and several spots of green algae. My FC was 10 and CYA 60 when I returned. My pool only gets a few hours a day of direct sunlight and is completely shaded or partially shaded all day except between 2:30 and 4:00pm when it’s mostly in the sun (which is why I haven’t upped my CYA to 70, FC seems to hold all day). I run my pump and salt cell 24/7. I monitored my pool via my blink cameras all week and it never rained while we were gone and the pool wasn’t used. This isn’t the first time I’ve had algae spots. Last week we got a ton of rain and salt and CYA levels dropped and the pool got a bit hazy. I noticed a thin layer of algae on the entire bottom of the pool, like a layer of dust gets kicked up when I brush it, so I started a slam last night. I don’t get though how I can up my chlorine to 12ppm, come home and find algae at 10ppm.