Just an update since it's been a while.
Still getting a lot of diatoms on the sand. And still not having a lot of luck with fish. My Earmuff wrasse, at least, is doing great. I have a Vanuatu hooded wrasse in qt. I was originally planning to prophylactically treat all if my fish for ich but I think I'm just going to do an observational qt +prazi instead. I just haven't been having any good results and felt like my healthy fish were dying just from the treatments even though they were relatively low stress treatments. It's starting to get really discouraging, and since I'm still taking risks and not qting corals or inverts I think doing ttm copper or cp are all excessive for fish that are showing no signs of ich. I'm not saying an ich free tank isn't worth it but I just don't have the resources to do it right now.
I added a few conchs to help with the diatoms (plus they are really cool). I also added a red and white Feather duster, and a neon green toadstool. I've started dosing Phytoplankton 2x a week to help boost my pod population and to feed the corals.