I agree with Watermom.

Also, your TA is very high as well. That is, in part, a function of how high your pH is, and, if you test TA when the pH is (briefly) in the right range, you'll see it's lower, but still too high.

What you need to do is get your TA 'way down, which means adding a LOT of Muriatic Acid. I'm guessing you have a shotcrete/gunite/plaster pool (as opposed to vinyl or fiberglass). This allows you lower your pH safely to levels in the high 6's without danger of harming the surface. I'm not sure how much acid you need, but you can figure that out easily. Your waterfall will aerate it back up. But you should aim for the low end of TA--probably 80 at the highest. This should help keep pH down.

I strongly suggest you consider the 50ppm level for borates in your pool as well. With the lower TA, a borate level of 50ppm, you should have the dual effect of controlling your pH better and fighting off algae better. It seems to really help pools with your problem. This will use a lot of both borax and Muriatic Acid, and you have to get your FC under control as well.

Since you are still swimming, I'm guessing you are in the more Southern regions. Therefore you should consider raising you CYA to a level of at least 50ppm and trying to maintain FC there. Even up here in NJ, I frequently raise my CYA to the 40-50 level because of UV chlorine loss. And aylad, my fellow Mod, keeps hers in the 70-80 range in Louisiana because otherwise she faces what you face, with FC.

But you gotta get that pH down because with pH that high, the chlorine is far less effective, as well.