Sex ratio in Pelvicachromis genus

[coenga]

Hello everybody,

I'm still wondering and working on sex ratio in Pv genus.

My experience is poor, but with two different Pv teaniatus morphs (moliwe and dehane) I've allways been on the mâle side of the force...
And this with slightly acidic water pH 6.5 and temp between 23 and 26 °C.

My last batch is nearly sexable and I can count 4 females for 28 males which goes for a 1/7 f/m ratio.

What I know and think that is true (but not sure), is that higher ph and lower temp goes favoring males. Is that your experience ?

Actually, I'm lowering the pH with ro water changes and I'm know around 6, waiting for next fry session...

any datas and comments welcomed,

best regards,

Colin

 

[Randall]

pH and Pelvicachromis Sex Ratios

Dear Colin,

We've often heard that with Pelvicachromis pulcher and P. sacrimontis a lower pH favors females and a higher pH favors males. This has been my experience as well.

Although, I don't have any personal experience with temperature and sex ratios, some Apistogramma specialists have expressed that lower temperatures tend to produce more females, and higher temperatures tend to produce more males. My Pelvicachromis species are consistantly breed in water that is about 76-degrees F., so I have no basis for comparison.

Please share your results with us.

Thanks!

Randall Kohn

 

[Sam]

sex ratios

I live over a limestone aquifer, and my water comes from there. With P. pulcher I have always gotten a sex ratio skewed very heavily towards females. I don't have any hard data except that from a recent spawn of seventeen fish, only three were males. I keep my tanks at 76-78 degrees fahrenheit. I don't know why this is. Also, females are more common than males in the lfs in my city.