sexing convicts when young

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Hwom91

Gambusia
MFK Member
Sep 30, 2009
245
0
16
Oregon, IL
My convicts have about 100 fry right now(big surprise) and i was wondering if i would be able to sex them early. They are about .25", so still young. I have some that have not colored up yet, they are just whitish in color with no stripes. Are these the females? or will i just have to wait till they get bigger. Thanks for the info.
 
The only thing I could say is the bigger ones should be males. That's not 100% but a good start at this size.
 
ok. so why are some of mine a yellow/white color? they look almost albino but that cant be right.
 
they are probably just the non-dominant ones, fry will change colors/patterns alot depending on mood, they are def too small to sex thats for sure, i think some females start to get orange on their bellies at like 1-1.5in but someone correct me if that is wrong as i havent personally seen ones that small
 
If your fry are white/pink or yellowish-white, and the parents are Black Convicts, then I assume the parents carry the pink/white gene, hence some fry are coming out as white/pink. The white/pink fry will most likely be white/pink when fully grown, hence they will never get any black stripes. If the fry are greyish with black bars, then they are black convicts.

I just gave away 60 convict fry at 1 month old that were free swimming for 3 weeks only. All the ones I gave away were black---meaning they were grey with black spots on them at that size. Almost half the fry were white/pink. These were the ones that I kept. The parents are black, but the mother carries the marbled gene, since her father was a marbled convict, hence his daughter is producing some white/pink fry.

Make sense?

At 1 month, you should be able to identify them between white and black cons. You wont be able to distinguish sex until they are at least 3-4months or almost 1 inch.
 
ok. Thank you for explaining that. I knew the mother didnt mate with a pink convict because this is the 3rd batch they have had.
 
I've breed convicts currently. At that size, you cannot tell them apart although as one person said, males will typically grow faster. Once they get bigger the females will develop an orangish patch on their abdomen and will have more color in their fins (blue and yellow). The lighter ones you speak of could be less dominate fish, but it is possible you have some pink strain in them (not albino because the eyes have normal color). But you will definately be able to tell as they get bigger as the pinks will have no stripes and will be "pink". The pink gene is carried by the male. My male is striped but not to the degree that many of his off spring are.
 
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