I recently purchased a coral beauty for my tank. It was quarantined at my lfs and it looked perfectly healthy when I bought it. It’s been 4 days now and it hasn’t eaten any nori that I put in the tank, and only picks at my rock. He’s developed a white streak down his sides and I’m worried about what it could be. It’s difficult to take a picture because he hides underneath a rock arch most of the time but will also swim like he’s perfectly healthy. My main concern is that he doesn’t even acknowledge any seaweed that I offer on a veggie clip. Any thoughts on what the issue is?