I've never used sand for any of my animals for the simple fact that sand can cause impaction. It happens to regularly for me to put my animals at risk. Before using a dirt mixture, I used wheatbran. The same easy spot clean that sand has (even absorbs moisture) and it's also digestable. But After reading Robyn's posts about his success with dirt, I thought I'd give it a shot. I use a clay/sand/soil/virmiculite mixture. Since I got my uros (even before switiching to dirt) I've kept a monthly check on their weights and length. One month on dirt and ALL of them put on better then 10 grams in weight, were more active, Eatting MUCH better, and even their color improved. I'm convinced, My uros convinced me, that dirt is the way to go. As you can read in my post above yours, I recently switched them over to a 125 gal tank with about 5 inches of dirt in it. In the week they've been in there, They have tunnels running throughout the tank. If that doesn't prove they're happier, what does?
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2.0.0 Iguanas, 3.4.0 Beardies, 1.2.0 Saharan/Nigerian Uromastyx, 1.1.1 Leos, 0.0.1 African Fat Tail, 0.0.1 Fla Garter Snake, 0.0.1 Corn Snake, 0.0.3 Fire Belly Toads, 1.0.0 Eastern Painted Turtle, 0.0.1 African Sideneck, 2.1.0 Horses, 2.2.0 cats, 0.1.0 dog, and I'm done for now.....