dwarf platys, male vs. female

[Tostada]

I saw some dwarf platies at the LFS today and they seemed really cool. I thought I might add a couple to my main tank ... or, seeing as they're so small, maybe I could have a couple by themselves in my new 5.5 gal.

I can't tell them apart, though. That's pretty much why I got swords in my main tank. I always heard with swords that you either want all males, all females, or at least a 2-to-1 ratio of females to males. So my main tank has 2 males and 4 females.

But what about dwarf platies? I assumed the same guidelines apply to platies, seeing as they're almost identical to swords, but I can't tell male from female. I suppose females should be a little more rounded, but there's already enough size variation that I can't quite tell.

Any advice? Would 2 females and 1 male work? That doesn't seem like enough for a schooling fish...

Anyway, fishprofiles.com says males have a "modified anal fin," but I didn't notice anything special.

 

[Zagz]

The bottom (anal) fin, if it is fan like then it is female, if it is straight, it is male. for a 5.5 gal I would leave it at 2 females and one male. Keep in mind though you will need another tank for the fry you will most likely end up with.

 

[hsherman1986]

i have a few dwarf platies, and telling them apart by the fins like you would in guppies, mollies, platies, and swords is the same with these platies. The ones with the rounded/fanlike anal fins are girls, and the ones with the straight, pointed fins are boys.

Be careful though, if you buy them too small, you may end up with all boys. They will change sex on you. Used to have two boys and two girls, now I have three boys (one of them died, not sure if it was a male or female that died)

 

[Alshain]

If you had 3 male then it was probably a female and got overstressed. I'm surprised the males didn't kill each other first though.