One more update for now. I got pretty frustrated with daily dosing and measuring numbers, with the results and numbers just never making sense. I actually came pretty close to just quitting altogether. So I decided to throw a Hail Mary.
Looking back at all my previous builds, this is the only one that I put a skimmer in. So I took the skimmer out completely and replaced it with Chaeto. Within two weeks, the recession on one acro stopped (though it still looks pretty rough), the bleaching on the Frogskin acro is almost completely recovered and it's bright green and beautiful again, and I have some very tiny PE that I hadn't see before. Zoas and Grandis are more open, and Duncans are wildly happy. And my chalices have some new PE as well. The scoly is probably toast, but it was looking pretty rough, probably worse than the worst Acro. The Poci's recession also recovered completely and there's new encrusting as well.
I can't explain this with numbers, and for whatever reason my PO4 still measures zero, with very little difference in algae growth. The chaeto is quite happy, so far. My nitrates were a little high at 20, but Im waiting to see how that changes as the chaeto grows.
Looking back, I remember barely coming to the conclusion that I would run a skimmer on this build. I think the only reason I chose it is because everyone else usually does, and I had the budget for it. Now I regret it. Maybe Im wrong, its only been a couple weeks, who knows, but Ill see how this does over the next few weeks and we'll see.