I disagree with not keeping them in a cichlid tank... they generally ride the surface of the water and stay out of the cichlid's way. Me and a friend of mine have both kept needlefish in our 50 gallon tanks for multiple years with numerous cichlids including firemouths, convicts, mbunas etc.
IMO they go with any fish that won't fit in their mouths. They won't bother anything larger and generally nothing bothers them since they stay out of the way. I even had a figure 8 puffer with mine for a long while and the puffer didn't fin nip him at all, although the puffer did eat out my senegal bichir's eyes eventually(bye bye puffer).
