Temp vs male/female ratio...

[John7]

I have recently decided to keep the smaller cichlids as opposed to the bigger ones and have been blessed with a small spawn of Kribs. I have about 40 fry now after 4 weeks. They are doing very well on micro worms and frozen BBS with some fine flake food being thrown in now that they are getting larger [3/8"].

My question is, does the temperature that the eggs are incubated at determine the ratio of females to males or is it the pH? I assume that it is more desireable to have an abundance of females rather than males, is that true?
John

 

[M0oN]

I've been told that with apisto's the temperature is what determines sex ratios, 76 gives fairly even, below gives more females above gives more males...

I'm unsure if this is true for kribs or not, but thought I"d mention it.

 

[kribber]

For selling the fry it would be desirable to have and equal ratio of male to female fry.
I personally like more males because it is harder to find nice ones and with more male fry there is a wider choice (imho that's if you are planning on holding any back for future breeding purposes). I find that the females are more consistently nice in their coloration.

 

[Neil]

kribber,

WELCOME TO THE FORUM

In Pelvicachromis, pH seems to be a more widely acknowledged factor for gender determination. But I have had experiences to lead me to believe that it is not a fool-proof method. 76-78º with a pH of 6 to 6.5 is probably what you should shoot for.

Slightly more females would be advantagous, IMO, because pulcher have both monogamous and polygamous reproductive strategies.

Neil

 

[kribber]

Thanks for the welcome Niel.
When you gave the ph and temp parameters was that for an equal sex ratio or skewed for m or f?
I find that kribs are so easy to breed that I don't worry if the are monogamous or harem breeders. My experience is with small tanks and I find the females are not tolerant of other females in their space. I would rather divide a tank and have 2 peacefull pairs than try to juggle a trio that may not work out. Separate pairs also allow for greater genetic diversity. I am new to fish breeding so I like to keep it simple.
It is easier to find good looking females in this neck of the woods but quite difficult to find nice males.
Now I need time,space, and money for grow-out tanks.

 

[John7]

Kribs

When my fry start to stray I placed my mated pair back with the original group of 10 kribs that I bought some time ago and now find that they are starting to defend another barnacle in the group tank. :lol: Soon I will have another batch of fry and a decision to make on where to put the other eight kribs while the parents tend the new family. :?

I recently found and bought four albino kribs at an auction. 8) They turned out to be two males and two females, and seem to have decided to make two pairs. Things are looking good for some albino fry in the near future.

I read somewhere that the males of both color variations prefer the albino females, but the albino females prefer the regular males over the albino males. :? Does anyone have any opinions or info on why that would be?
John