Anyone know if you can use an exo-terra desert heater on a plastc container with a lot of sand? I am worried te heater will melt the plastic....any idea?
You should use sand. Put him/her/all of you geckos (if you have anymore) on a solid substrate, like paper towels, newspaper, ceramic tile, etc. Get a rheostat of the web and that will control the heat of the UTH so it won't burn the gecko.
Assuming Brad means that you should(nt) use sand hes pretty much correct as its a hazzard to the gecko/s especially at a young age... using a UTH under a plastic tank can be very high risk especially if the plastic tank isnt a large one, but aslong as you have some form of temperature control i.e. a thermostat you should be fine, the best you can get with a UTH is a " Mat Stat"..... Adding extra substrate wouldnt really make a difference as it could still melt due to the UTH being on the outside of the tank providing you have this correct positioning thus the heat is contacting the plastic before diffusing into the substrate and above into the atmosphere...
Even though all the zoo-med UTH's say "use on glass only", I have read in their advertising that the mini (1-5 gallons) was made to be usable for plastic containers. I use these on my 10 gallon set-ups that I sell people because I find that in the 10 gallon glass bottoms with a tile substrate the temp doesn't get much above 92. I have used these mini heaters with the plastic critter keepers with a thermostat with no problems.