Pictures of other species here
Dermogenys pusillus male.
The female halfbeak (foreground) is noticeably larger than the male, and also paler in coloration
Fishkeeping Facts and Tips
Too many fish? Overstocked tanks stress the fish in many ways: competition for food and space, bullying from other fish, deterioration of water quality and increased concentration of disease vectors. A lightly stocked tank will always be easier to care for, with more stable water quality
Have a look at some of these related sites