Finding the Right Enclosure
When considering cage size, it's vital that you know how large your iguana is going to grow. Green Iguanas can reach a length of five to six feet in just four to five years, a fact that many people don't realize when looking at tiny little hatchlings. Your iguana should be able to stretch out to his full length in any part of the temperature gradient throughout the cage, and this is impossible with a small cage. The minimum cage size should be:
Materials you can use to make your enclosure include wood, glass, Plexiglas, hardware cloth, and plastic coated wire mesh. Never use glass or Plexiglas if you plan on putting the cage in direct sunlight, as they do not provide proper air circulation and temperatures will be too high.
The enclosure should have a tight fitting lid to prevent escape and smooth sides to prevent injury to your iguana's feet, nose, and tail. If you are using wood, be sure to seal it with a waterproofing agent and caulk all of the joints to ensure that you can properly clean the cage. In warm areas of the country, you may want to build a walkout enclosure to allow your iguana access to the outdoors.
Placement of the Enclosure
The temperatures throughout the cage should range between 84° and 90°F, with a basking area that is 90° to 100°F. Nighttime temperatures should be between 70° and 77°F.
Primary heat sources can include a series of incandescent bulbs over the enclosure during the day, nocturnal bulbs at night, removable heaters under the tank, and ceramic infrared heat emitters or panels.
Secondary heat sources are generally a 50 to 75 watt incandescent bulb in a ceramic base or basking lights. The area heated by the secondary heat source should only cover one spot that is approximately 25% to 30% of the total enclosure space.
All sources of heat should be outside of the enclosure, either under the floor or above the lid. This will prevent your iguana from accidentally burning himself. Hot rocks should never be used.
There are two types of light you must use during the day - visible light and UVB light. Sources of visible light include incandescent bulbs and fluorescent lights for all areas of the enclosure. These lights generally provide heat as well as light, and the areas they cover should overlap so your iguana has equal access to both. Lights such as the Zilla Tropical 25 UVB Fluorescent Coil Bulbs, can provide UVB light. UVB light is very important for the synthesis of Vitamin D, and it ensures that your iguana can metabolize calcium correctly. UVB light cannot pass through glass, so if you use these lights, you must use a mesh top on the enclosure. If you rely on sunlight for UVB, you cannot house your iguana in a glass cage; it must be in a wire cage.
To maintain humidity levels, always keep a bowl of water with a large surface area in the enclosure. A large surface area ensures that it will vaporize more quickly. You should also mist your iguana and the inside of the habitat several times a week. Always use a hygrometer to monitor the humidity in the enclosure.
Suitable substrates include paper towels, brown wrapping paper, Astroturf, indoor/outdoor carpet, and alfalfa pellets. Lineoleum can also be used as long as it is glued down with safe glue. If you use Astroturf or indoor/outdoor carpet, be sure to have extra pieces so you can put a new one in while you are cleaning and disinfecting the old one.
Avoid the following substrates: pebbles, bark, rocks, sand, cedar shavings, gravel, corn cob, cat litter, wood shavings, and potting soil with vermiculite, pesticides, fertilizer, or wetting agents. All of these substrates are unsafe for your iguana to ingest, and they can cause damage to the intestines or impactions.
Plants & Accessories
You should also place a number of branches in the habitat. Green Iguanas are aboreal, and they will spend a lot of time high up in the cage. The branches will be used for climbing and basking, and there should be places throughout the various temperature gradients in the cage. Use branches that are at least as wide as the width of your iguana, and avoid using wood that oozes pitch or sap. Oak is a popular choice.
Finally, your iguana will need at least one hide spot. The hide should have a snug fit, and it should be placed high in the enclosure where iguanas spend most of their time. Your iguana should be able to fit his entire body in it, but it does not need to be long enough to cover the tail as well.
Other items you can place in the habitat include securely anchored ropes for climbing and flat bottomed, smooth rocks for basking and climbing.
Green Iguanas have very specific housing needs, all of which you must meet if your iguana is to stay healthy and safe. There is no cheap shortcut to be found, and a good custom or homemade iguana enclosure can cost anywhere from $300 to $3000 depending on the materials you use and the complexity of the enclosure. Before deciding whether or not to bring home a Green Iguana, we encourage you to determine whether or not you can afford the time and money it takes to house them correctly.