difference of fish

Question
What is the difference between male and female red eye tetra?

Answer
As far as I am aware of, it is very difficult to nearly impossible to know the difference between male and female red eye tetras. The only sure way to know, while it is still difficult, is when they spawn the males are thinner than the females. However, even during spawning it will be difficult to know for sure. There are some fish you can easily tell the difference between male and female and there others you simply cannot. I hope this helps. Let me know if you need more help.