Well, things conspired against me and I had to leave to pool unattended for a few weeks. A light dusting of mustard algae on the bottom greeted me, despite my SWCG keeping around 4 ppm chlorine.
After measuring my CYA my mustard algae shock level (from the table here) was suggested to be 39!! So, off the Walmart for bleach. I dropped my pH to 7.2, raised my FC to 35, plus I dumped in a few ounces of some non-foaming algecide (HTH) I found at Walmart. I brushed the sides and bottom and attacked the area under the steps as well. Plus I tossed in all the floats and toys.
I must have hit the pool chemistry like a sledgehammer because the bottom cleared literally within 3 hours. Ran the pump overnight with the SWCG running at 40% also. Then went back to my normal 8AM-7PM hours.
Over the next three days I allowed the FC to drift down to about 13, where it is now. Brushed each day, backwashed filter yesterday. Never recorded any CCs during this process nor any FC loss overnight (once I went back to my normal filter hours, so the SWCG wasn't adding FC overnight).
borates - 50 ppm
So far, the pool is spotless and sparkly. I will maintain FC around 10 through next week and then let it drop back to 4-5 for the rest of the summer.
Am I doing this right?