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Re: (sex ratios)

George Slusarczuk wrote:
> 
> Hello yungfamily,
> 
> Very interesting, but you neglected to give us the pH of your water!
> Also, what is "more water changes"? Once a week? Daily?
> 
> Best,
> 
> George S
> 

> > HI!
> >
> > A friend and killie mentor gets a very screwed (towards male) sex ratio
> > w/ many of his nothos.  He raises them w/ peat and rarely does water
> > changes (pH probably gets very low).  He had lots of problems w/ N.
> > rubripinnis.
> >
> > I'd always wanted rubripinnis (my 'dream' fish), so he gave me some
> > eggs.  I raised the fry without peat, and did more water changes.  This
> > probably kept the pH higher.  The result was that I got almost an even
> > sex ratio.  (where as he got almost ALL males except for maybe one or
> > two females)
> >
> > I've noticed that ALL the nothos I raise either have an even ratio or a
> > ratio w/ more females, never more males.  That is, except the time I
> > raised N. guentheri like how the friend I mentioned above does.  I got
> > all males, except maybe a 2 or 3 females.
> >
> > The marked change in sex ratios may not have anything to do w/ the pH.

First, the other guy's water and mine were basically the same (lived in
about the same area, came from lake Ontario - i think).  I just tested
my water, and the pH is about 7.2 or so (probably there's slight
differences during diff times of the year).  I don't know about the
water changes - I do them when i feel like it (maybe once every couple
weeks).  However, it's still more water changes than the other guy - I
think in one tank housing a pair of sjoestdti (spell?), he hadn't done a
water change in almost a year.

Remember the science project i mentioned before?  The outcome was
something like 1 male:19 females in the 8.4 pH tank and 5 males: 14
females in the 6.4 pH tank.  Notice that in either case, the females
still outnumbered the males by quite a bit.  Therefore, I believe that
pH is NOT the only thing that descides whether the nothos are male or
female.  I think it may be a combination (like what Mr. Watters
mentioned), and maybe I have the right combination to produce more
females, and my friend has the right one to produce more males.  Just
what I think...

NN (i.e. notho nut) Sam
References: