Very nice looking cage . This type of cage design works fine in areas with mild temperatures and naturally high humidity but kept indoors in houses which are air conditioned or heated (both which dry the air) they can be very hard to heat/humidify .
Most of your heat is rising (moisture too ) and going right out that screen top .I'm guessing it is roughly 4' in height by compairing the stuff you have in it . If so this is about twice the hight you will ever need even for an adult tegu of the largest species (they are not arboreal so they only really use the floor space in the cage ) By going with a more solid top (just a narrow strip for ventilation and small ventilation holes in the sides you can get good cross ventilation , reduce your heat needs and make it much easier for you to maintain your humidity .(Check out Vision's six foot cages to get an idea of how much ventilation you will need at the top - I used these Vision cages indoors and had small vents cut into the sides and they were very easy to heat and humidify )
The hide box although very nice looking is way too tall again allowing any moisture you spray in that area to just rise to the top .
The hide box doesn't need to be any taller than 2" or so more than your tegu is high on an adult tegu (Their burrows in nature are not very high ... maybe to keep predators out but one main benifit they get from less height in their burrow is higher humidity )Also if that is terra cotta it will soak up any moisture you spray in that area (pot will be damp , mulch will be dry )
You can get that same look by using the saucers made to go under those pots depending on how large your tegu is (they come in plastic too which will hold your humidity up better ) If you prefer to use clay for the look you can have the pot sealed with a water based varnish or line it with a plastic one just slightly smaller in size . (if using varnish make sure it is completly dry and there is no smell before using it in your enclosure .. this can sometimes take weeks or more depending on the type sealer used )
Increasing the size of the water bowl in a tegus cage to raise humidity is like asking for trouble . Larger bowls are harder to clean . We tend to not change them as often as we should increasing their risks of getting bacterial infections from drinking water which they themselves have contaminated . I never use anything larger than the standard size dog bowl for my largest tegus (you do not want them laying in it .. messing in it and drinking it )
It would be much safer for your animal to purchase a humidifier and run it in the room in which the cage is kept ... humidifiers also have the nice benefit of making your own skin not so dry in the winter months and making it a little easier to breath . the one drawback to using a humidifier I have found is you have to keep them very clean =)
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Stella St.Pierre
www.bluetegu.com