How long to determine sex of fry?

[dnaelting]

We have had a few batches of guppy fry and a couple batches of swordtail fry. We are wondering how long does it take before you can tell the sex of the fry.

Both types of fish have very obvious visual differnces between the sexes, but how long does it take before those differences show?

 

[Puriti]

I have a 2 month year old baby molly and I couldn't tell very well til about 2 weeks ago ....>> when he started to try to breed my females.

 

[whitetiger_CJ]

yeah, I would say about two months will be average for most live bearers. your ph may also determine the ratio of the males to females.

 

[FawnN]

You should be able to tell within 2 to 3 months. Most of the time you can tell by the colors. The males tend to be very colorful with more finage.

And then there is the more obvious signs of a male. The male's modified anal fin, which is called gonopodium.

 

[dnaelting]

whitetiger - how does the ph affect the male/female ratio. I have high ph, at about 8.

 

[FawnN]

It's also the water tempt that determines the sex too.

 

[dnaelting]

OK,

So if I have a ph around 8 and a water temp about 80, what will I get more males or females?