Bearded Dragons, Uromastyx, and Arid Reptiles
Very dry and hot. Low humidity. Possible to have a diverse cleanup crew with careful planning.
Go with the Straightforward Choice for a simple cleanup crew or the Advanced Ecosystem suggestions to take your bioactive ecosystem to the next level!
Straightforward Choice: Springtails
Entomobrya unostrigata (Cotton Springtails) - Thoroughly proven as the best true arid springtail. E. unostrigata are often unavailable online so a common secondary choice is Entomobryoides purpurascens (Wood Runner Springtails).
Advanced Ecosystem: Springtails
Mix Entomobyra unostrigata and Seira brasiliana. Introduce P. violenta under the water dish. Unfortunately options for maximizing biodiveristy in arid environments is currently lacking, but see the full species information list for picking additional species.
Straightforward Choice: Isopods
Porcellio dilatatus (Giant Canyon Isopods) - The best combination of arid survivability and cleaning ability.
Advanced Ecosystem: Isopods
Mix Porcellio dilatatus and Porcellionides pruinosus. Unfortunately options for maximizing biodiveristy in arid environments is currently lacking, but see the full species information list for picking additional species.
Quantity
Quantity of springtails and isopods required for a bioactive enclosures varies based on enclosure size and the amount of time the enclosure is establishing before adding the main inhabitants. As few as 50-100 springtails and 10 isopods per species could seed a 4x2x2ft arid enclosure. Unfortunately it is hard to provide springtails and isopods favorable conditions for growing into high and effective populations in arid enclosures.
Crucial Information
It is impossible for any springtail or isopod to survive long term in an arid environment without a hydration station, that is, an area of permanent moisture. The simplest option is to put a thick layer of sphagnum moss under the water dish which is kept moist at all times. To increase the activity of the cleanup crew, place various sphagnum moss hydration stations throughout the enclosure, such as little caves filled with moss or even pockets of moss buried in the soil. More hydration stations also means more potential to add species diversification. The water bowl itself will not suffice for a hydration station as springtails can't lay their eggs in water and isopods cannot navigate hydrating their gills in a water bowl without potentially falling in and drowning.
Additional Information
Always provide a thick layer of leaf litter for the cleanup crew to hide in and graze on. For a naturalistic look, I recommend adding crushed maple leaves on the floor with live oak and magnolia leaves on top. Fallen leaves make up a large part of the isopod diet and soft leaves like maple are their preference. Springtails will also graze on the maple leaves as they decay. Ideally, the soil in the enclosure should have some detritus (like compost) for an additional food source. If mixing up your own soil blend, add crushed leaves and white rot wood to the soil or purchase a high quality compost or topsoil to mix in. Detritus as it breaks down further is also food for your plants. Supplemental feeding with fish food is a great way to keep the cleanup crew population thriving and ready to tackle the main inhabitant's waste.