It looks like everything is OK. Unless you want to pursue using a PO4 remover now, I don't see a reason to do so.

But . . . it looks like I'm going to be putting together a 'winterizing kit' containing PO4 remover + a clarifier, with the intention of selling it to up to 100 in-ground pool owners who want to avoid spring-time slime. I hope to make an announcement about this by mid-August.