Feeding in a separate tub is fine, there is no added stress, and it also helps reduce accidental food bites. My first snake was a Red Tail Boa (a young one, not full grown). This was way before I ever had a computer or knew about the internet. I used reptile carpet and fed in the enclosure. Trigger would reach up and snatch the mice from my hand, they never touched the ground. How cool to have a snake that hand feeds! Until I wanted to take him out to hold him that is. As far as he was concerned, if it was entering his enclosure and was warm, it very well might be food! I got bit pretty much every time I tried to pick him up. Never made the connection between my feeding in the enclosure and the biting when trying to pick him up. As for the Aspen, if you get the nice clean shredded kind it holds tunnels really good. There are some cheaper brands now, I forget the brand that really holds tunnels good, it's very light in color and finely shredded. The other advantage is that if you put a nice layer down, it turns the whole enclosure into a hide, because he can go under the Aspen. This helps him feel secure and thermoregulate at the same time. You do need to watch the UTH, Aspen will hold heat. Put your hand under the Aspen right on the glass over the UTH and be sure you can hold your hand there. If it's too hot then get a rheostat, or if you still have some of that carpet, you can lay the carpet down and put the Aspen over it. Just be sure he can't get under the carpet. The rheostat is the safer way to go. Good luck!

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Lyns Lair
Frogwatch USA
WNY Herpetological Society
0.1 Cat (Mia)
4.2 Ferrets (Wolf, Shadow, Verdell, Sullivan, Boo, Peach)
1.0 Carpet Python (Bear)
1.0 Malagasy Blonde Hognose Snake (Wilbur)
1.0 Yellow / Everglades Rat Snake (Pumpkin)
1.0 Russian Sand Boa (Fang)
0.1 Normal Corn Snake (Mysty)
1.0 Anery Corn Snakes (Suezo)
1.0 Banded Water Snake (Ripley)
0.1 Golden Greek Tortoise (Sunshine)
0.2 Mississippi Mud Turtles (Squirt & Shyanne)
1.0 Green Iguana (Norbert)
1.0 Whites Tree Frog (Trevor)
2.0 Solomon Island Eyelash Frogs (Chompy & Gimli)
1.0 AFT Gecko (Cocoa)
5.5 Leopard Geckos (Trouble, Scooter, Simba, Firenze, Teddy, Mystique, Freckles, Dotty, Zipper, Twister)