trilineatus

Hey guys,   I got two new cory trilineatus for my trilineatus/betta tank the other day. Both showed signs of stress, as can be expected, but right now I'm watching my original two and one of the new ones chowing down on a sinking shrimp pellet together. However, the other new one isn't fairing...

Alright, about a year ago, I bought 4 cories from a LFS that is very poor at identification...  3 were in one tank marked "large cory" and the smaller one was alone in a tank marked "small cory".   At the time, I thought they were all trilineatus, but the one was younger than the rest... over...