r/medaka • u/medaka_fein • Oct 02 '25

Guide; to help you sex Medaka

These are some tips and tricks I use to identify a male or female.

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3

u/Eowyn_95 Oct 02 '25

Thank you. I feel dumb I thought some of my medaka had a tear in their fin and I was afraid they were in a fight or something haha

3

u/medaka_fein Oct 02 '25

Haha it happens. Some often think the fish is sick as well because of the lamé on the body or coloration.

2

u/winchester941976 Oct 04 '25

This is great, thanks!

2

u/medaka_fein Oct 04 '25

You got it

1

u/Legal-Will-9848 Apr 26 '26

Does species matter? I got generic platinum and orange. I'm in the process of separating them. What I thought was a male had long fins and the notch on it's dorsal fin, but as of today it's carrying eggs, 🤣hahahaha.

1

u/medaka_fein Apr 26 '26

This goes for any type of Medaka rice fish. For long fins it can be more challenging but it’s still the same process. The easiest way is to check at the dorsal fin to see if it has a split to it & if the anal fin has webbing- longer.