Stratty
0
Looks exactly what I have battled last year. I had a CYA that was WAY high due to some bad advice from a pool store before switching to the trouble free pool method. SLAM it making sure to measure carefully with your new kit to capture any overnight chlorine loss measurements. I have a sand filter but opted to vacuum straight to discharge as I needed to replace lots water to get the CYA down to a reasonable level. It does go away after a successful SLAM, my pool is proof of that.