sex ratio

[trev1]

Just so i am clear guys, does ph determine sex or temp?
I am new here and have not read this info yet..

trev

 

[nellyfish22]

From what Uwe Romer mentions in his books the sex ratio is influenced more by temperature than p.h. For 50/50 sex ratio's he suggests a temperature of 26'c and from what i have seen with my fry it is pretty accurate.

 

[Mike Wise]

Römer's studies were for Apistogramma. Each genus probably has its own factor(s) that influence sex ratios. Back in the late 70s, Dr. Loiselle wrote that pH was the primary factor in Pelvicachromis species.

 

[tjudy]

pH is an important influence on sex ration for Pelvicachromis, but I suspect that temperature is also an influence. Sex determination in this genus is still poorly understood.

 

[bigbird]

Hi all,

Just to add some comments, I have 2 tanks set up with Endlers guppies, one at 26C and the other at 24C. With 24C I have more female fry with ratio of 70-30 to the females and at 26C I have more males at 70-30. Is very interesting to watch. cheers jk

 

[wethumbs]

I concur with 'Bigbird' that temperature can be a factor. I deliberately raised the temperature on the same parent of P. taeniatus from 78F to 84F and resulted in a 3/1 ratio of male to female. While the normal spawn from this pair's yield is 50/50.

So temperature is definitely a factor.