Acceptable substrates are newspaper, newsprint, paper towels, indoor/outdoor carpeting, vinyl flooring and alphalfa pellets.
Stay away from reptile bark, sand, gravel and corncob substrates because iguanas eat these and this may cause a blockage problem, requiring surgery. Use of cedar chips can be fatal. I also recommend not using the new aspen bits as a substrate.
Use diluted bleach for cleaning cages and water bowls and disinfecting logs and other cage furnature. Nolvasan (chlorhexidine) is also recommended. Never use Lysol(Alkyl)or Pine-Sol which are toxic to iguanas. Never mix bleach and ammonia together, as this can be fatal to the iguana and the owner.
You may have noticed that iguana poop is almost impossible to get out of clothing and carpets. Bleach works well on white shirts. Try Oxi Clean on colored clothing and carpets.