Just an addendum, after sticking to the plan and keeping FC around 7, the pool has looked absolutely awesome for the past 10 days. It went from me not being able to see my wife from 6 feet away underwater to me being able to see a diving stick at the bottom of the 9 ft deep end from 50 ft away with no problem. Lots of empty 182 oz jugs of clorox in the garage. So thanks on that one. And for whatever reason, the filter has now built pressure and purged all the funkiness when backwashed, so it's working a-ok.
Just a question. I had the tub of Leslie's granulated chlorine out by the pool sitting idle, and I figured I'd throw in a scoop because I was temporarily out of Clorox, and boy does that stuff really makes the water dull and cloudy. Not cloudy like "i can't see anything" but it definitely looks dead compared to sticking with the Clorox. All my end-to-end top-to-bottom sparkling is drastically reduced. I guess I didnt realize before that the actual granulated chlorine was part of the problem, as far as the look of the water. It's definitely clearer after 24 hours, but I will never put another scoop of that stuff in. What is it in the granulated chlorine that causes the water to look so poor compared to just rocking the straight up Clorox?