Sexing Zebra danios

Quoting from http://www.fishpondinfo.com/danio.htm#sex

Males are more slender and sleek. Mature females are fat, especially when egg-laden. In the ordinary zebra danio, the males' yellow white areas (stripes and on the dorsal fin edge) are a much stronger yellow. Males tend to be smaller and more vibrant in color. Females full of eggs will have an enlarged ovipositor (where the eggs come out).
 
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