Yellow Damsel being bullied! Please help!

[xjaredx]

I have a 10 gal tank right now. The fish that are in it are a Tomato Clown, a Yellow Damsel, and a Strawberry Psuedochromis. I started out with the clown and damsel first, and then introduced the strawberry a while later. The strawberry has since dominated the tank, but has only really picked on the damsel. Today, I came home from work and the damsel was missing half of it's tail (the fin part at the end, not the part with any type of bone).
I did not see this happen, so I do not have proof of the psuedochromis doing this, but the yellow damsel was actually cowering behind the clownfish the whole night. I separated the two, and have kept them separate, but now what should I do? Is there medication I should give the Yellow Damsel for it's tail? Should I put the psuedochromis back in? Is there any reason this would happen besides the other fish attacking it?

Any help on this would be great. Thanks a lot!
-Jared

 

[johnanddawn]

psuedochromis are very aggressive and you need to either remove it or the damsel. but be advised even though tomatoes can generally hold their own in a small tank like that it will be next in line. psuedochromis need a species tank if they are to be kept in a nano

 

[Angel]

Sounds like it could be a territory issue, especially in confined areas, such as a ten gallon tank.