The box

He/she should stay to the iguanas inside a box (an aquarium to raise fish, a wooden box or of grills, etc.) the sufficiently big thing as to run, and high so that they can climb. For a small iguana, a box 70 cm. long for 70 of high and about 30 cm. of bottom. The iguanas are not as the fish that stop to grow if the aquarium is very small; the iguanas will grow, not caring the measure of the box. They love to climb, for that reason it is necessary to place inside the box thick branches, in those that can support the body completely, very firm so that they don't fall. The iguanas will jump of a branch to other, and they will also use them to take refuge. It is also necessary to place some object in which can hide, as stones, tree barks, or a dry cactus to enter inside. Lastly, if it fits inside the box, you can place a small hibiscus, somewhere around the iguanas will climb and they will also devour since it their leaves and they love their flowers. 
It is recommended to sometimes take out the iguanas of the box so that they can run free for the house, and to climb the furniture. They also sell some small belts that don't hurt the leather of them to walk them for all sides.  
The sustrate of the box of the iguana is the floor that is used so that this he/she is not directly on the floor of the box, that is to say, on the grill, the glass, the wood or what is the floor of the box. The used sustrates is sand, gravel of fishbowls, chip, tree bark, or dry leaf, etc. Included paper, since is easily disposable, cheap and very manipulate, but not of newspaper (newspaper) neither others that contain inks, since these, they could affect its skin. The stones for cats are not a good sustrate since these certain chemists they possess to eliminate the scents of the feacals of the felines and they could damage your iguana. 

The Temperature 
The iguanas need the heat to be able to be developed, since these they don't take place, they regulate neither they maintain their own heat for their metabolism, but rather they receive it from the means. They also need it to digest the food appropriately and to fight against the illnesses. The heat activates the bacterias that the iguanas have since in the stomach and intestine these they begin to consume the fibrous part of the vegetables, what helps the iguana to digest these nutrients "premasticateds". The iguana should have a terrario that maintains an approximately superior temperature to the 30 grades C (28-32°C), but she should also have an area but fresh where she can refresh, since they autoregulate her temperature moving among sectors with high and low temperatures according to they need it. 
The box of the iguanas should remain hot, this can be for a radiant heat from above them (you can use an small vial common of 60 W (bulb of 60 W)). The light should be separated from the iguanas for a grill (to avoid that the iguana burns), with the small vial (bulb) to several centimeters of the grill. The iguana will try to remain more so the near the small vial that can, if you/he/she is possible, inside the box you/he/she should be placed branches and sticks so that this I/you/he/she ascends for them and I/you/he/she can arrive near the heat. 
The heat you can also achieve placing a badge low calefactory a small pile of newspaper paper, so that this isolates the iguana of the end heat and avoid that this he/she dies or suffer damages product of the burns. This is what Hot rocks happens to the calls that have direct contact with the iguanas and they acquire very high temperatures for the iguanas. I don't recommend to buy these stones calefactories, yes the badge calefactory that can be isolated and it is more economic; for who have already acquired a stone calefactory Hot rock, I recommend them to cover them with goods or newspaper paper if it is possible and not to light them for more than 7 hours a day. Also, these "Hot Stones", they could electrocute your iguana if she defecates on the electric stone. 
To measure the heat inside the box, it is necessary to acquire a thermometer, and the temperatures should oscillate between the 28 and 32° C. In summer it is very easy to reach these temperatures, so practically it is not necessary to not even place the badge calefactory in the night. 

The Humidity 
The iguanas also need water in the atmosphere, as humidity to maintain fresh their skin. The small plate with water, with the heat inside the box, it can maintain a high humidity when evaporating the water, or if not, water can be tossed inside the box with a sprayer. A good humidity is between 70 and 95% inside the box. 
Some iguanas like to have a great source with water to swim, and this the humidity also increases inside the box. A good idea to maintain the high temperature together with the humidity, is to place a test tube with water (of those that are used in laboratories) and I penetrate a heater of those used to heat the water of the fishbowls. The heat increases the environmental temperature and he/she makes that the water evaporates increasing the humidity. 

The Light 
The iguanas need direct solar light, meaning, solar light that doesn't pass over the glass of the box, neither the glasses of the window of the bedroom neither neither a plastic. They will need at least, 30 or 45 minutes to the day of solar light, especially in summer. 
Also, during the day, inside the box it will need an ultraviolet light UV-B. No common small vial can give them light UV-B, not even the acquaintances as "wide spectrum", so it is needed to have a fluorescent tube that this designed for light UV. This light should separate the iguanas for a grill NEITHER PLASTIC NEITHER OF I GLAZE since these they block most of the light UV-B. In the market these lights are known as Vitalite (I don't know if it is mark or what). This tube of light UV-B should not be replaced by the small vialwith neodymium, since these can only be used to increase the heat but it doesn't stop to produce light UV. 
This light UV-B, either direct of the sun or of the fluorescent tube UV-B, is necessary for all the organisms because it is used at intestinal level to activate vitamin D (the one that we ingest in vitamin precursors' form), the one that is necessary for absorver the calcium of the diet. 
He/she remembers that the vitamin D is very difficult of giving in direct external form, since an on-suplementación of this vitamin it is disastrous for the health of the iguana, but when the vitamin D is synthesized starting from precursors activated by the rays UV of the sun or coming from the specialized fluorescent tubes for this, they don't suffer damage since some this vitamin production D it is used for its complete benefit. 
In any event, the iguanas although they have the tube of ultraviolet light, they need direct solar light, especially in summer, when the solar light is bigger. 
But besides the light, the iguanas also need of the darkness. For this, it is necessary to cover the box of the iguanas so that they can have as minimum some 8 at 10 hours of darkness every night. 

The Air 
The same as all the vertebrates, the iguanas need to breathe oxygen, therefore, it is necessary that the air among easily to the box where the iguana was raised. For this, coarse to open the cover of the box slightly, if it is that he/she has it, and to avoid that yes that the humidity descends too much for this entrance of air.