The problem that most iguana owners run into is false information on the subject of enclosures. The word "Tank" shouldn’t even be said about an iguana that is over 1 year old. They simply don’t make aquariums, "Tanks", big enough for an iguana over this age or around 6 inches svl (snout-vent-length). If you MUST start off with an aquarium, start off with at LEAST a 55-gallon aquarium. This is still not big enough for an iguana that is any bigger than 5 inches svl. Iguanas need large areas to roam and enormous areas when there bigger. I would recommend building an enclosure from the start. First of all, make it as big as you can afford, in space and money. You can make this out of wood plastic whatever you like. Make sure there is enough ventilation. I recommend using a covered top because it helps to hold in the heat MUCH better. You should put ventilation holes in the sides of the enclosure. Remember, iguanas love to climb and be up high so it would benefit your iguana if you make you enclosure as tall as possible. Iguanas feel safe up high so put branches and shelves near the top of the cage as well as the bottom. You should point the basking lamp/lamps at the shelves at the top as this is were your ig will want to be. I prefer using some sort of clear glass or plastic for the front of the enclosure as this will help keep in moisture and heat.

A grown iguana will most likely need an enclosure the size of a small room when they are near full growth. For an iguana that is anywhere from 7-14 inches in length I recommend these dimensions: 6 feet high, at least 5 feet long and 3 feet deep. These are just rough estimates but it should give you an idea. For an iguana any larger I recommend 6-7 feet high (or as high as possible) 8 feet long, 4-6 feet deep. These are MINIMUM sizes. These are also for an iguana that is allowed to roam free for some of the day to get exercise. If your ig will be spending all, or most, of his time in the enclosure than the enclosure should be bigger. My iguana is only 10 1/2 inches svl and she has her own room to herself (see free roaming).

As for substrate, never use any type of particular substrate! These are easily eaten and can cause impactions, which leads to many, many problems including definite surgery to remove it. I would recommend using paper towels or plain old terry cloth towels. I personally use green terrycloth towels. You can also use indoor/outdoor carpet but I don’t recommend it because the carpet will unravel and the iguana can eat this and get an impaction.

You should always provide some sort of hiding box. The iguana needs a place to get out of sight and light. You can provide this by putting a plain cardboard box in the enclosure with a hole cut in it or you can go buy one of the half log hide boxes at any pet shop. You should also provide the iguana with plenty of things to climb on such as branches, ropes, cargo nets, etc.