Hey,
Because your racer still is young, he will do fine in a 10 gallon. Just make sure whatever thing you put in there with him is not from the wild and if it is than put it in the oven for like 5 mins to kill germs or mites. And make sure you never use anykind of ceder as it is deadly to most any animal. I would not put too much in the cage, because racers need a little room to move and if there is too much he will be crouded. I would use pine bedding, sand, non treated potting soil. With a little hide box and a few fake plants, a rock for shedding and good looks, a water dish at all times, heat lamp on him 12 hours a day with a 60-75 watt bulb in it. Usually if you can tame the racer first they will eat for ya. And because he is so little i would just feed him crickets. Because my little eastern yellow bellied racer is feeding on them now. And as he grows i will get him pinks. So if you follow this stuff he should do just fine, and if he is aggressive, just hold him with gloves 5 mins a day for a week or so. And once he sees that you are not gonna hurt him he will stop biting and stuff. If you need more info or questions just email me, wchuntsman@msn.com. THANKS, WILLIAM H. AND THE GREEN PINE MUSEUM.
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