How can I determine the gender of Neon Tetras?

Question

In my aquarium are some Neon tetra.

(source: wikipedia)

I'd like them to breed, but I don't know if they can because I can't determine their genders.

After careful observation, I can identify some females (they have a larger belly). Are there characteristics to help me tell which is which?

Answer 1

Other characteristics

• The male is slender and the blue line is straighter while The female is rounder producing a bent blue line.

• Mostly, the males are bigger than females

Also see : How to Tell If a Neon Tetra Is a Male or Female?

Answer 2

Males do tend to be more slender and females a bit rounder, but honestly, with a large enough school, you'll probably end up with a mix of both sexes anyway. I like a school of at least a dozen. The fish seem to be more at ease in a larger group, and with more fish, you have a better chance of getting a mix of males and females.