I have 1 male 9 months old that is 300g already. I have 1 female that is 395 grams already that is also 9-10 months old. The female is a lot longer than the male but same thickness. I wonder if some BPs are like dwarf retics? Some stay smaller while others over achieve in size. All 3 of mine are healthy just the girls are longer. My girl Miss Snow is 615 grams now but is not fat she is long. I am guessing (not experienced in raising BPs) that if on a healthy feeding diet they grow as they should and more/less as food is available to them? Not an expert. My boy sheds on the same day as my female that is same age as him. I have had them for 2 shedding cycles now. They both are healthy eaters. Best wishes with getting him back on track. I am sure if he eats he will grow.