blotched anthias too skinny

[Rain2387]

Just got a 2.3" blotched anthias from shipping. Found it has a really sunken belly. Otherwise it's eating pellets normally when I put it in the isolation box first. Should I be worried? what might be the cause of it?

 

[Mr. Mojo Rising]

Feed it 3 or 4 or more times per day, anthias eat a lot, they are always hungry.