One of our males is not eating. Now, this time of year is most likely the reason, and our other males do the same.

However, the problem I'm faced with is: He is now down to about 800-850 grams. His spine is becoming more pronounced, and I'm worried about his health.

On top of that, about a month ago I could have sworn I saw him going into shed, and yet nothing has happened...but his color is still darker. I've never had a retained shed this bad, and he's not eating at all to gain any weight to make him go into another shed.
Now, this could still just be a play on my eyes, but all of these things have me worried.

All our other males are fine, just this one seems to be having issues.

Sorry for the all the writing, just wondering what everyone else suggests. He isn't going in with any females at all, and we offer food ever week still.