Naso Help

[bkelly]

only just noticed it this weekend , i was away and come home sunday thats when he seemed off. he sure looks thin. I had some cyano grow up over the weekend, had done a 20% water change before i left, the skimmer was fine and i tested last night for nitrate and ammonia there was none detect, my pH is 8.3 and KH 9 , salinity 2.025 im going to do a water change tonight again, not sure if thats it , all other fish are fine , corals seem ok. I think maybe its cause i was only doing once a day feedings, although he was eating wekk last week and always the first fish to greet you, now hes looking thin and spits out what he eats. my other tangs are fat. the tank volume is 180 gal, ive had the fish 4 months , he was an adult i got from a friend shutting his system down.