Fighting newts

[eminem]

Hello everyone, I have 2 fire bellied newts one is much larger then the other in i think a 10 gallon tank, when ever I feed them the big one will attack the small one and I have to break it up. These arent just small fights either the big one will grab the small ones legs or bite its face and do a death roll (similar to alligators) what should I do? I am also afraid that the small one is so small because the big one is eating all the food also I dont want my small newt living in fear of the bigger one, they have lived fine together for almost 7 years and this has just started happening for about the past half year

 

[AngieD]

Are they definitely fire bellied newts?

 

[eminem]

yes well they are black with a red stomach with black bloches on it