Hi everyone, I've been learning here for years first time posting! I'm in a serious battle with some brownish colored algae. Pools been open for 2 weeks now, water is clear and my tests are pretty much dialed in but can't shake this large spot on the shallow end floor. I even broke down went to the pool store and bought a bottle of silverside algaecide . It's been 3 days since I dumped the whole qt in and algae is growing. I've scrubbed every inch of this pool for 2 weeks and have been brushing the algae spot 3 times a day. If it wasn't slimed I would almost think it was a stain at this point. I don't know what else to do. 10 years with this pool and never had any issue like this whatsoever, Please help!!!
FC: 6
CC 0.5
PH: 7.5
CH: 200
TA: 100
CYA: 40
FC: 6
CC 0.5
PH: 7.5
CH: 200
TA: 100
CYA: 40