the substrate question is as "controversial" as the temperature question : )
i am not a fan of dry substrates at all. a good soil substrate, one that allows the animal to dig and burrow as they need, provides a moisture gradient, which is as important as keeping a temperature gradient.
with a good soil substrate, you have a relatively dry surface (but not as dry as paper, liner or tile) and a moister underground where the animals can dig, hide, shed, lay eggs, etc.
it is all a part of a larger picture. overall husbandry is a puzzle with many pieces, all are significant.
i have seen many, many lizards kept in a dessicating environment, just too dry, and they live in a constant state of dehydration. over time, that leads to organ failure, body failure, and death. that may take 2 months, that may take 2 years. one day you look in the cage and see "acute death", that is, the animal is dead with no outward signs. more often than not, that is organ failure. whether related to low temps or dehydration, the body just can't take it anymore and gives up.
as for the inevitable impaction question : )
with a dessicating substrate like playsand, or even tile, a dehydrated lizard can get impacted with lots of things, including simple foods like crickets and certainly the sand itself. it simply doesn't have the metabolism to pass things. that is complicated more when temps are too low to keep the engine running smoothly.
after keeping hundreds (thousands?) of lizards on a good moist substrate like soil, i have never had an impacted animal. as they say, they could eat and pass doorknobs if you set them up properly. certainly in the wild dragons are not falling over dead impacted from the very earth that is all around them.
as for the poster that apparently thinks i am a "know it all"...
why would you say that? you say that because i am discussing husbandry issues you are not familiar with? why be so negative? the forum is about husbandry, is it not? to exchange ideas and have a discussion.
post a productive response, just read, whatever, but don't just post to say "that guy's a real jerk". i'm not a jerk, i am passionate about reptiles, reptile husbandry, and seeing keepers have success. i spend hours posting in various ks.com forums, just not usually here : )
if i didn't care i wouldn't post, i wouldn't put tens of thousands of words on my site that get even further into husbandry issues and theory. i wouldn't spend the last 15 years trying to learn from, promote and support the reptile world. i'm no bad guy.
the bad guys are the ones that sell reptiles and give no support at all, just a "have fun, and let me know when that animal dies in 2/3/6 months, i will sell you something else".
no disposable animals. learn and grow. great reptiles for a great experience. let's be about that : )
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robyn@proexotics.com
Pro Exotics Reptiles
