Urgent Care :: Help please!

[Lulu]

I have a couple of questions actually but here's some of the basic info first and a bit of a back story...

I have 2 turtles that I got a day apart from a pet store that was selling smaller than legal size babies (about 2".) I got them both out of the same tank at the store.
Now a year and a half later they are in a very large clear rubber maid container with a large floating rock, basking lights, water heater and filter.
I can't remember exactly what size the tank is right now but it's large and just temporary until I get the acrylic personalized tank I want to have made.
Anyways one of them is about 6" long (Male) and the other that I got the very next day out of the same tank is still only a little over 2". I have researched and researched why he isn't growing and the only thing I have found is that it must be malnutrition, HOWEVER he is and has been eating the amount he should be eating, I have continued to keep him on the hatchling pellets thinking that would be better for him. SO my question is does anyone have any other idea what might be going on and why he is still so little? Any insight is greatly appreciated! It's been a joke around our house that he's just a dwarf and something genetic is keeping him small, but all of the research I've done has said that's impossible it has to be malnutrition.

Now on to the extremely important question...
Tonight I glanced over at them and the larger turtle was biting the small ones shell above his tail trying to drag him off of the basking rock, I of course immediately jumped up and got him away from the little one. THEN I noticed the little one has a chunk of shell missing from his right side between his front and back legs. It's obvious the big one bit him.
I have removed the little one from the tank and put him in a box with a clean towel in the bottom after running him under some water to make sure the bite was as clean as I can get it w/o messing with it too much. He's not bleeding but there is one spot in the missing chunk that is a pinkish red. I am desperately searching for a vet around here that deals with reptiles but until I can find one any suggestions would be sooooo greatly appreciated!!!
Thanks so much in advance for any help!

[marisa]

Are you sure he had the same amount of food as the larger one when they were smaller and growing? Were they fed separately?

Stress can compromise growth, and it sounds like the little one could have been intimidated by the other. I'm guessing that the space was inadequate for the both of them, which led to bullying. How many gallons is that container? From their sizes, they should ideally be in an 80-gallon enclosure...

Now that the little one has been injured, he should remain separated from the other one with his own enclosure (and equipment). Turtles with major size differences shouldn't be kept together. If you kept them apart until the smaller one was more the size of the other and wanted to try to house them together again, they would need a really large enclosure with hiding spots, etc. (bigger than 80 gallons, since they would have grown). Even then, though, there's no guarantee that there would not be bullying and aggression.