Just recently took over caring for a pool (care taking estate)
The pool company was doing it and I watched what they did for some time before I volunteered to take over. They came once a week and poured some chlorine and acid in and ran their Hammerhead that made it all cloudy and that was it.
I found this site and got a K2006 kit and found that there was almost no calcium, the TA was extremely low and 0 CYA
but there was never any algae problem while they maintained it. After I took over it bloomed yellowish green. I slammed it for three days and it got crystal clear. Then I made sure that the FC level stayed between 3-5 but in a few weeks it started to get green again.
I don't understand what is going on. I thought if the Chlorine level stayed up at all times this could not happen.
Because the CYA was at 0 I used the tricolor tabs exclusively for chlorination and Taylor FAS-DPT kit was daily assuring me the levels were good
Now I'm back slamming and am also confused about the proper slamming level. In one place it read 12 PPM, in another I read 20-30 PPM. I have been going for the 20-30 level but it would be nice not to have to use so much.
I see that it is relative to CYA content but am still confused
I think I have some CYA now (the dot almost,maybe,pretty much disappears at a full to overflowing tube) which would be 30
SO……..any suggestions/advice on PPM for slamming and explanations for the recurring algae?
BTW it's a 25000 gal tiled pool w/sand filter and ancient 1hp pump
I got the calcium up to 190 and TA up to 90 so far