Just called out by a very reputable local hotel to save them.
30x50x4 plaster pool.
83 deg F
Primary sanitizer is tabs.
Yesterday, day one, I put in 4 gal liquid cl (12%) to take my fc to 27 ppm which would be shock level according to the kick but cya/cl chart that I live by (thanks!!!)
I have 20 lb of dichlor mixed in a bucket ready to add tonight because MOST of these green pools I respond to have an algae bloom in process and I can usually shock it back to great. But even after taking it to 27ppm yesterday, it dropped back to 15 today and I'm 2nd guessing myself because it had no visible improvement whatsoever in 24 hours.
Should I shock it tonight or am I looking at a different issue that I'm unfamiliar with?
Water is green, hazy, can barely see side ladder steps, can't see MD. Water does not look swampy and algae filled necessarily...
Copper? Algae? ***?