Whoa ... biggest Indotestudo elognata in the world! Not even Colossochelys atlas, the biggest tortoise ever to have lived (probably 1 ton) could get that big. Sweet picture, though. Cute and scary at the same time. :)
If you recently got him from a pet store, then odds are he really does need to fatten up. For one thing, he's wild-caught, which means he was shipped here from Central Asia for 7,000 miles in a crate. His fat reserves may have been okay in the wild (not necessarily), but they probably weren't...
I think it's normal if they are too lean and need to regain some weight. Hopefully, once they get to the point where they're well fed, they won't need to eat all day long. Of course, don't be surprised if they still have big appetites at mealtimes. :)
Oh, man. I always confuse toxic creeping charlie with the edible mallows. They look so much alike to me. Is there any good giveaway to tell the difference?
PS - Makes sense why your tortoise loves them so much, since they're mallows. :)
Looks like creeping charlie (Glechoma hederacea), which is in the mint family. Herbivores don't typically eat mints, because of their strong flavor and toxic compounds. I wouldn't worry about it, though. After a couple bites, your guy should learn to leave it alone. My female Russian did (the...
A couple possibilities:
1) Both could be desert tortoises, but as mentioned above, the lighter one could be a Mojave desert tortoise (Gopherus agassizii), while the darker one could be Sonoran desert tortoise (G. morafkai). Is that it?
2) It could be that the lighter one was raised...
That's too bad. However, even if you were to house them together, you'd still want a quarantine period of several months to make sure they were healthy and not likely to infect each other. I would house them separately.
Box turtles are terrestrial pond turtles, so they are rather different from true tortoises. Boxies typically like the water a bit more than tortoises, and their diets are different, too. Tortoises are essentially herbivores, while box turtles are essentially omnivores. Whereas your Russian's...