ok.. i am gonna try and be nice about this...
it needs be eating more than one circket a day!!!!!!!!! how big ?? bigger than the space inbetween its eyes? it should be eating as much crix as it can handle in 10 mins.. which with the way my beardies eat would be anywhere between 80-100. you can also feed them twice a day.
secondly have you taken him to the vet to rule out parasites or anything else.. beardies can hide syptoms very well, he may not look sick but very likely could be.
thirdly are you keeping him hyrdated and supplimented with calcium d3 every day to every other day .. and a mutli-vitamin as well.
his basking temp should be 100-110 degrees.. this way they digest their food more rapidly and hence grow faster
and IMO i wouldn't be keeping him in a ten gallon tank.. it is hard for the beardie to escape from the basking heat if he is in a cage soo small.
and are you sure he was 12 weeks when you got him and not like 3 weeks or something.. because most beardies are 5'' stl when they are born.
let me know if i am forgetting anything
ALSO cv768 ---- i know this is the wrong forum but to save myself some time.. i would think for a trio of basilisks nothing smaller than 250 gallons.. ingo was probably giving you good advice with 400 gallons.. he is very knowledgable about them.. and i have some issues about the dog food... but if you want to discuss that you can e-mail me privately
alissa