Platy/swordtail Fry

[amy1994]

They are only 2cm, it's the smallest i have ever been able to tell whether they are male or female.
Mainly males again...
Does anyone know why this is? Is it the temp?
I always have mainly males for platies, and mainly females for swordtails....its strange

But i finally have a black swordtail boy

Can't wait to see what he looks like when he's older.

 

[OldMan47]

I can't say why you are experiencing mostly male fry. I have much the opposite in my various Xiphophorus species tanks. I find that I have more females than I really want. It is known that temperature during gestation can affect sex ratios. What temperature are you keeping your tanks?

 

[amy1994]

I can't say why you are experiencing mostly male fry. I have much the opposite in my various Xiphophorus species tanks. I find that I have more females than I really want. It is known that temperature during gestation can affect sex ratios. What temperature are you keeping your tanks?

25C

 

[OldMan47]

25C is a bit warm for many of the more common swordtails and platies. I try to keep mine closer to 21C. The less common wild type species each has its own best temperature but what we see in pet shops are mostly hybrids of various distinct species of Xiphophorus.