My ocellaris pair hosts in a bta, they were in within a couple of weeks. I still don't know if this had anything to do with it, but I put some pictures of false percs hosting in anemone's on the tank where the fish would see them and they went in. It could be a coincidence, but it's worth a shot. Although mine host, I've heard others say theirs don't so it seems like it depends on the fish.