The green iguana (Iguana iguana) has reached legendary status as the most popular reptile pet. In the wild, green iguanas range from northern Mexico to southern Brazil and Paraguay.
Since males can grow to 6 feet in length and females can grow to 4 feet (both at an alarming rate of speed), a 40-gallon terrarium is the best choice when selecting a first cage. Once the iguana outgrows the terrarium, it will be necessary to replace it--usually with a custom enclosure. The cage should have a selection of strong branches and plenty of vertical space for climbing.
Approximately 40 percent of a green iguana's diet should consist of dark, leafy green vegetables. Other vegetables should make up another 40 percent, with juicy, fresh fruit making up the last 20 percent of its diet.
A high temperature gradient is important for iguana digestion. An overhead light source is the most natural way for iguanas to receive heat. The cage's temperature should range from 75 degrees Fahrenheit at the cool end to 95 or 100 degrees Fahrenheit at the warm end. At night, the temperature can drop to about 70 degrees Fahrenheit.
Indoor iguanas should have a full-spectrum bulb included in their cage setup. If possible, iguanas should be housed (either temporarily or permanently) in outdoor enclosures, as natural sunlight is extremely beneficial to this species.