If you don't want to have problems with your tegus toes use Cypress mulch , Eucalyptus mulch , Hemlock mulch , or Orchid Bark .
These mulches are all safe for reptiles
...when lightly misted they hold a good ambient humidity
... their texture helps to slough of old shed from the tegus toes
... they do not readly grow mold like many other types of bedding
... they do not clump up when moist and stick to the tegus feed
... they are realativly easy to find in garden centers (Home Depot , Lowes , Target , Walmart etc.) and are usually a lot less costly than most other beddings .
Keep 3-4 inches of the mulch in the bottom of your tegus cage and pack his hide box with it so he can dig around in his hide box . ( I don't keep more than 4inches of mulch in any tegu cage I have including adults - this is plenty for them to dig around in ) Change the mulch frequently . If you want you can clean the mulch and reuse it over and over again (get yourself a screen that you can put it on and hose it down good .. put it in a bucket and soak in a little bit of bleach and water .. put it back on the screen and hose it down very well to remove all the bleach .. let it dry fully in the sun before you reuse it )
As far as using garden soils go in tegus cages it's more trouble than it's worth . Most garden /yard soils are not suitable for tegus (if you can't grow pampass grass in it your soil holds much to much water - pampass grass needs even moisture and can not tolerate having it's feet wet - these are the plants that grow where tegus make their burrows ) Clay type soils will dry hard on their toes , loams hold to much water , most sandy soils are loaded with nematodes (at least they are in FLorida where I live ) I don't even use soil in my outdoor cages for my adults - if I used my garden soil my lizards would have constant skin problems . I use 3-4 inches of mulch in most of my outdoor cages , I do have a couple with play sand but I hate it cause it is messy and the lizards do not do any better on it . If you want to use a soil type mixture buy sterile play sand sold in your local garden center but this is very messy indoors .
As far as keeping your humidity up in most areas of the country you will only have to lightly mist your hide box once or twice per week even with central ac and or central heat running . The idea is to lightly mist and then let it dry out a bit before doing it again .
There is a lot of mis information on this forum . A lot of people give advice to use stuff that they have not thoughly tested . They don't do it out of malice , they do it because it is working for them right now but seasons change , enviromental conditions change so what may work for one person one month may cause them a whole lot of problems another month . I have tested just about every type of commercial bedding available on tegus and have never found anything that consistantly works better for them than these mulches I listed above.
Cypress mulch is a totally non toxcic wood . It grows in a swamp where they harvest the roots that rise above the water . For this wood to be able to survive rotting in this constant wetness it has to have natural properties that fight off fungal/mold growth . In many other countries where water is a precious (rare ) resource roofs of houses are built of of Cypress to collect the water for drinking .
Stella St.Pierre

BlueTegu.com - Ron St.Pierre
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Stella St.Pierre
www.bluetegu.com