Melanotaenia praecox is a small rainbowfish that maxes out around 3", often staying even smaller. Males are electric blue in the body with cherry-red fins; females are duller but blue nonetheless, with yellow fins. These beauties are the perfect rainbow if you don't have the space for their bigger cousins!
These are juveniles around 1" long. Their colour is developing, but they need time and good feeding to reach their full potential.