Weight concerns for 3-4 yr old BP Hi All,

I recently adopted a 3-4 year old BP from a friend of a friend. 

Just from a day's worth of research we knew immediately that he wasn't properly cared for. (He was in a 10 gallon and no thermometer hydrometer, 1 hide, etc. Very sad looking little dude and retained eye caps -- were working on that). We've gotten him everything he needs following ataraxia's guide. 

Anyway, he's about 3 or 4 and we've had him for about 3 days. His weight is at 628.5g and he's about 2 and a half or so feet long. 

Is he underweight? How much should he weigh? 

Thanks! 