Are the 2 white lines horizontal and extend back from just below the gill plate in the middle of the body? If so, then thats normal for Yellow Tangs. It becomes more prominent when the fish is scared, asleep, sick or not getting enough algae in its diet.? Or is it by the fishes lateral line which could be head and latereal line disease-HLLE. This is due to poor water quality and poor diet. What are your nitrates, ammonia, nitrites, pH. SG, and temp? Are you feeding any frozen algae like formula 2 or angel food diet as well as spirulina flakes or pellets to your tang? _________ 75g reef with Nova Extreme 8 bulb HO T-5 lighting, refuge, Remora skimmer, DSB, Seio powerheads, Acro's, LPS corals, assorted zoo's & mushrooms, Yellow Tang, Maroon Clown, Blue Cleaner Goby , Cleaner, Fire and Sexy Shrimp, Coco Worm, T.Crocea Clam, Derasa Clam
120g FOWLR, 260w Orbit power compact lights, Remora Pro skimmer, 30g DIY Sump/Refuge, DSB,Seio Power heads, Powder Blue Tang, Purple Tang, Flag Fin Angel, False Eye Puffer, Copperbanded Butterfly and a Moorish Idol  |