Acually the little damsel is not bad at all. I wouldn't put more in there, but from what I understand a little gobie would be fine also. I just do a water change about once a week. The water was in good condition. Like I said, I just moved everything over to a 10 gallon. And I got a little clown. I am going to get another, and some sort of anemone for them to use as a host.
Ben