Have you read our care sheet, written by Rich? >
Green Ig care
There are also many excellent websites around. Have you been feeding anything other than the foods you mentioned? Igs need a large varied diet, consisting of many veggies and fruits (see the care sheet and websites for full lists of food stuffs). Iguanas are quick-growing reptiles, and with a proper diet and the proper care should do very well. What is your enclosure like and the conditions?
There are several experienced members on here who know a lot about igs,,. change your ig's diet, and i'm sure one of them will be on soon to fill you in more about anything you need to know.
Just to check the growth rate - have you got any kind of weighing scales and a tape measure? Sometimes when an animal is in our care and we see it every day it is difficult to notice a size change, but that doesn't mean that it hasn't grown. The best way to know for certain is to regularly weigh and measure the length of your ig, then you can know for sure and perhaps you'll see that he has grown.
Also, remember that every animal is an individual and will grow at different rates. To check the health of the animal and ensure that no parasites are present take a faecal example to the vet, but other than that if it is receiving the right UV and food it should be fine. Just because the others in the shop seem to have grown more than yours doesn't mean that anything is wrong.
