A transient parasitic infection (maybe the ick got in his balance system)?
>>Doubtful, I’ve not read of such mild infestations affecting an animal’s balance. If this were a problem you’d see flashing and rapid gilling, not just balance problems. >What scares me is that this might be a buildup in the Caulerpa toxins. >>Possibly, but again, I do doubt this. I didn’t have a problem feeding C. taxifolia to my Z. flavescens, Z. scopas, or other tangs for several years. >I give him a little bit each day as a treat. He loves it. (Won’t eat any kind of Nori, broccoli, spinach, Sprung’s sea veggies, lettuce, spinach, bok choy etc. for greens). >>Again, he will if he’s hungry enough, and again, offer him some meaty foods.