My name is XXXXX XXXXX I'm a biologist with a special interest in reptiles. I'm sorry to hear of this problem.
I 'm sorry to give you bad news, but I believe you deserve honesty. Being lethargic and not wanting to eat are classic signs of illness. Most Russian tortoises are wild-caught. They're then transported in crowded, dirty conditions, and transferred from one location to the next until they finally end up in a pet store. Many of them are sick and infested with parasites at that point. For that reason, I recommend that any new tortoise be taken to a reptile vet right away for a check-up. The vet can check for parasites and provide treatment if needed. There may be other health conditions that also require attention. This link will take you to directories of reptile vets:http://www.austinsturtlepage.com/Info/state_resources.htmhttp://www.nytts.org/nytts/helpnet.htm
The other option is to return Clyde to the pet store. Even if you get a different one, it would be a good idea to have it examined by a vet, and quarantined away from Dimitri. You also will want to keep a close eye on Dimitri in case he already caught something from Clyde.
The only things you can do to support Clyde at home are to double-check your lighting and temperatures to make sure they are right. The gradient in the enclosure should be 75*F to 85*F, with the basking area warmer yet, at 95*F. Night temperatures can go down to 70* to 75*F. If your UVB light bulb is more than 6 months old, it should be replaced. They are ineffective after 6 months, even though they may look fine.
Providing soaks is a good idea, too. You can make them even better by using half water and half Pedialyte (yes, the kind for human infants). Soak Clyde for 20 to 30 minutes. This will at least prevent him from becoming dehydrated. Warm enough temperatures and soaks may make him feel a bit better, but I do suspect he is sick or has parasites.
If you have more questions, let me know in a REPLY. I hope that whatever you decide to do, it will work out well.
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