The last I recall from the other thread is that you have a light in the pool but didn't remove it to get into the light niche. There may very well be a lot of yellow/mustard algae lurking there which means that even if you kill it off in the bulk pool, it will re-introduce itself as soon as the chlorine level drops down below around 15% of the CYA level. It's one of those choices you have to make -- either find and kill the last of the yellow/mustard algae in all dark places it hangs out in the pool or deal with having to inhibit it with one or more of 1) a higher than normal FC that is 15% of the CYA level or 2) use an algicide (such as Polyquat 60 weekly) or phosphate remover at extra cost.