caymansarah

Hi - when I set up my tank I bought 5 female platys - because I know that they preserve sperm and therefore would breed without and that I would get some males in the spawn.....but I have around 20 fry and I cannot see a single male - my conclusions are that either - the sex doesn't become apparent until they are bigger (although I think that is not the case because I seem to remember having a male platy fry in the distant past) or somehow you need males in the tank for the fry to take on a male gender.....could that be the case? Or I suppose it could be that I am not very good at sexing - but I am pretty confident that I can tell the difference.

Can anyone shed any light on this...surely it is not a co-incidence that I have 20 female fry from 6 different monthers?

Llama

According to a book I have on livebearers...

It takes a few months for the anal fin to be modified so you can sex them. So you have to wait a bit.

dakotajim

How old are the fry? They can start breeding at 3 months, but I would suggest getting a male from another pet store anyways so you are not inbreeding too much. I usually try to get my males from a LFS and my females from a big box company.

caymansarah

Ah thanks Llama - that makes sense....

dakotajim - That option would be nice but we don't have that many shops here - the only other that I am aware of has fish that are always in horrid condition, sick and mixed with wrong breeds - so I don't buy from them on principle. I would love to have more options...

What I did do to try to ensure that the fish I originally bought were not related was i took one of each colourway so that I was sure they were from different parentage. I don't really need a male to be honest but perhaps when the sexes start revealing themselves, that might be the time for them to go to the store...or the males at least and perhaps keep my tanks as a Ladies Only tank LOL.

That said, I love when my fish are pregnant they look so round and healthy!

dakotajim

Yeah, we have lost most of the LFS in my town, just one left and they have a small selection. The big box guys have almost no swords. I was able to mix my platies from 3 spots, but my swords are all from the same tank, and they are not breeding either.

JChacon

No, there definitely doesn't need to be a male in the tank for them to be a male themselves. As the others said, it just takes a couple of months until you're able to identify their sex. They will usually look like a female at an early age, but you will be able to identify later.

prairielilly

Whether or not any animal is male or female is dependent on the type of chromosomes they have in their DNA, which is determined at the fertilization stage. It's part of their genetic makeup, so it won't ever change but may take some time to become visually apparent.

midnightwolf

is it the smae with sword tail fry?

ABCDemily

Takes about three months for the anal fin to change into a gondopodium, so I guess you'll have to wait!

caymansarah

ah ha! I have one called "Ansie" after my 2 year old son's teacher - it turns out that Ansie is a boy after all! LOL