spinos are a great fish, I have had a group of 4 in the past in one of my 75s. they are a central american cichlid get to be about 4 inches max, about as peaceful as they come, and have the unique trait of hanging their fry from floating plants much in the same way that bettas hang threir fry from the bubble nest.
EDIT:
I can't remember if they are still Archocentrus or if they got moved over to cryptoheros, when they reorganized the classification of many of the archocentrus species, though it seems that after a couple of years of stability they are really going at it again and will probably by the end of this year have turned all the groups around for the next couple of years