Hmm, that's good then - I've got some that are only 6 weeks old, but a few are absolutely rotund. Picture a tennis ball with mouth at one end and a tail at the other But I refused to truly believe that something 1cm long could be reproducing - (well, not without being an endler or similar )
Seem to be very healthy though - eating like little piggies, definitely not constipated or bloated, very lively, sociable and inquisitive. Maybe it's just the first part - the eating like piggies part that's the problem Note to self - cut down on rations