Re: only male fry

[Mike & Diane Wise <apistowise@bewellnet.com>]

It appears that your friends are rearing their fry in water that is too 
warm. Römer & Beisenherz (1995 & 1996) found that most apisto species 
produce mostly males when the fry were reared in temperatures above 
29ºC/84ºF. Apisto tend to have equal sex ratios when the fry are raised 
for the first 1 - 2 months at 26ºC/79ºF. In this respect, the 
temperature at the time of spawning is not as important as the 
temperature at which the fry are reared for their first few weeks.

BTW I think there was a typographical error in the answer you received 
about ppm. At low levels of total dissolved solids, 1 ppm TDS roughly 
equals an electrical conductivity of 1µS (microsiemen). 1 mS 
(millisiemen), or 1000 µS, roughly equals 1000 ppm. It is not an unusual 
mistake on emails. Many do not know how to type a micron symbol (µ)  & 
mistakenly use an "m" instead. The use of an "m", of course, represents 
"milli" in metric units.

Mike Wise

Dániel Gergely Faragó wrote:

> Hi All again,
>
> I think you shouldn't encourage me again to write. So I would have another question.
>
> I have some friends, who breed apistos. Lately they ran into a huge problem. The whole fry became male. It happend to A. atahualpa, and A sp. "Rio Mamore" (or A. maciliensis according to Römer). There were no females and nothing happend when they adjusted PH or other water conditions. This happend now for twice or three times. So what did go wrong or what can they do to have females as well?
>
> FDG
>  


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