I have an inground, indoor gunite therapy pool at my business. (Please disregard my signature at the bottom as that is for my pool at home). Recently, there has been yellowish staining along some of the walls and near the deep end that does not seem to brush off. The indoor pool is approximately 24,000 gallons and is sanitized with bromine tablet with an in-line brominator. The temperature of the water is maintained 92 degrees. The water was just changed out about 3 months ago and the current measurements are as follows:
It is an indoor public pool, generally we try to keep the FC around 2-3 ppm, but recently I seem to be having difficulty maintaining the levels consistently and seems to be dropping faster than usual. We have an extremely high bather load (150 bathers/week) so I am used to adding bromine tabs and liquid chlorine regularly to keep up, but it seems to be going through more than usual to maintain. It does have a few skylights so I thought that maybe the fact that it seems to be going through sanitizer quickly and the FC/Br levels are not maintaining and the yellowish staining on the walls that maybe I could have a mustard Algae issue??
I had the pool water (and the fill water) tested today at the pool store for metals and they said there were none. My questions are Do I have a mustard algae issue? If so, should I SLAM for mustard algae and then do an OCLT? What level should I raise the FC to if my CYA is 0? I read 12 for MA but that is with CYA at 20ppm. Or, do you think it isn't a MA issue and could I possibly have something else?
Thanks in advance,