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Re: Sex Ratios
Mike Jacobs writes:
>My A. cacatoidies (watch my spelling all the time....unintentional I assure
you)
>were spawning very successfully at a pH of oh about 7.7-7.8 and the the sex
ratio
>was 98% males
Uwe Romer and Wolfgang Beisenherz studied the effect of temperature and
pH on 33 species of Apisto fry and found that during the first month of
development low temperatures (below 76 F -- the "cool" test tanks were 74
degrees) produced more females. Low pH (5.5 and below) produced more
males, but had less influence.
Since Mike lives in Florida, his high percentage of male fry probably has
more to do with heat than pH.
My water parameters slightly acid -- typically 6.8 -- and about 78
degrees and my sense is that my fish produce generally even sex ratios,
though I often sell or trade fry before they are sexable.
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If wishes were fishes we'd all have ponds
Pete Johnson / San Jose, CA / petej@wordsanddeeds.com
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