A factor in iguana cage design that is frequently overlooked is ventilation. If your iguana lives in an "open-air" cage that is made out of wire or screen on the sides, ventilation surely will not be a problem for you. Even aquariums with screen lids usually have enough ventilation. Do not, however, use an aquarium with a full hood, such as is used for fish. These will not permit air flow in and out of the aquarium. We have all been in overcrowded subways or buses that were so stuffy that we thought we might suffocate. Now imagine the subway at a temperature of about 90 degrees fahrenheit, probably with food or feces at your feet. Your iguana would not like this scenario any more than you would! So make sure there is an air source in your iguana's enclosure. There are some aquarium-like iguana cages on the market that are glass on the sides and the top, with vents spaced around the sides. These cages seem to have satisfacory ventilation. However, if you have a glass top on your iguana's cage, ultraviolet light will be filtered as it passes through the glass. You need to have a cage that is well-ventilated and that is able to pass UV light through its top or sides.
By Melissa Kaplan