I have an iguana and I must say they are indeed interesting pets. First and foremost you must have a large cage at least 4 feet wide by 6 feet high my husband made ours. They need UVB lighting at to bask in follow the distance on the box. Ours is 12 inches from the basking spot. They also need a heat light at night they sell them in red or black or a heat emitter that needs to be in a special dome because it will catch on fire if it is not properly installed. They need branches to crawl on. They eat only vegetables and fruit and their diet should mainly be collard greens and mustards that is their main staple. I also give mine okra, carrots, once in a while spring mix as a treat without spinach, grapes, pineapple, watermelon, bok choy, snap peas, green beans. You can find the food list on green iguana society. Do not use commercial iguana food it is not enough nutrition. They also can not have any substrate in the bottom of their cage that they can ingest. I use reptile carpet. Do not let pet store people tell you any different because iguanas will eat just about anything. You give them enough food for them to leave some. First and foremost find a good reptile vet because they need one. Any signs of metobolic disease need to be treated and parasites too. MBD is a calcium deficientcy. Our iguana get prescription calcium. Those sold in the pet store have phosphorous and it does not allow the calcium to properly work. Their cage has to be kept warm but have a cool spot. 75 in the cool, 85 in the middle and 90 in the basking. They do NOT eat crickets. Iguanas are strictly herbivores meaning vegetarians. Any other questions you can email me at firstname.lastname@example.org.
Do not think an iguana does not have to go to a vet because they are born with parasites and although that is warranted in the wild it is not in captivity.
Do not feed them any other things other than what is on the green iguana society page.
Do not use hot rocks in the cage because iguanas do not feel they are being burned.
Do not put them in a 50 gallon tank and think they will not out grow it.