Tailed Guppies Sex

[bam_emma]

I think i have 1 male yellow tailed guppy and 1 female.
Because on 1 of them the so called 'Male' the fin on the top is much larger than the 'female'
Is this right?

 

[OldMan47]

Sorry no. The fins are almost useless to look at except when you look at the anal fin. The anal fin is the one right ahead of the tail along the bottom of the fish. On a female it is a definite triangle that is almost equal sized on all 3 sides. On a male it is long and thin and not at all triangular. When the fish are swimming close to each other, they are more likely to have their fins unfolded so its easier to tell the shape of the fin. Sometimes when they are off by themselves they will swim with the anal fin folded against their body and its harder to tell.

 

[bam_emma]

So its the same as the platys and the mollies??

 

[OldMan47]

Yep, same thing.

 

[bam_emma]

Cheers!
I've been trying to look but there too fast and sometimes they unfold their fin but i cant see if its a triangle