Since switching to BBB method last summer I am having a recurrent problem with algae just on the pool walls. It poofs up when brushed and is bright green. I will go through the shock process despite water being clear and cc 0 with no overnight fC loss. The chlorine did not go below 8-10 last 2 weeks (I have SWG by the way) and I kept it there and I still saw algae reappearing on walls. We brush once a week (I have a bad back). Filter pressure good at 10. From opening until a couple of weeks ago we even kept CYA at 55 and FC at 5 and we still got algae.
I am reluctant to go through mustard algae shock again on my vinyl liner as when I did that last summer along with pulling out pool light the algae still came back.
Note in my readings I have let the chlorine drop to 4 just because my husband doesn't like the chlorine so high (dries skin) and quite honestly it didn't keep the algae away. I did add polyquat after last shock.
I have a feeling our circulation is inadequate as we only have 2 returns plus pool vac return in a 30,000 gal pool. Should we just brush our pool more often and not worry about it as long as water is clear. I am just hoping to avoid that due to my back issues.
FC 4 (had been 8 at lowest)