Guppy

[Bobby H]

I had a large spawn of guppies, possibly from different parents. My question is they all appear to be females, is this common or even possible.  The fry are at least a few weeks old some maybe older

[Guppysnail]

Mine are a relatively even mix. I have read ph and temp affect sex as well as group ratio. I have no idea if that’s true though. 

Edited October 6, 2021 by Guppysnail

[Scapexghost]

Guppies and other livebearers all look female until the reach sexual maturity. Males aren't born with a gonopodium but rather the triangular anal fins that females have.

[lefty o]

you have to have incredibly good eyes to pick out the differences before they are a month old, sometimes a good bit longer.

[KaitieG]

I know you're supposed to use the anal fins to sex them--those all do definitely look female for quite a while, but for me in my own experience (a few hundred guppies so far) the females (pregnant or not) all have gravid spots pretty early on.  I hear that's supposed to be unreliable but for me it's easy and accurate.

[Bobby H]

Thanks all!  I am going by the anal fin so I'll just keep watching until I see the gonopodium, just want to try and keep them seperated

[Guppysnail]

On 10/6/2021 at 3:39 PM, KaitieG said:

I know you're supposed to use the anal fins to sex them--those all do definitely look female for quite a while, but for me in my own experience (a few hundred guppies so far) the females (pregnant or not) all have gravid spots pretty early on.  I hear that's supposed to be unreliable but for me it's easy and accurate.

This has been my experience as well. I can see that far sooner than the fin difference.

[Fonske]

On 10/6/2021 at 7:30 PM, Bobby H said:

I had a large spawn of guppies, possibly from different parents. My question is they all appear to be females, is this common or even possible.

From different parents, I would say it's very unlikely to have all females. From one guppy mom -  yes, it's possible. I once had a newly-bought female that dropped a small batch of 12 fry and they all grew up into unmistakable females. No idea why this particular drop was so unusual, as the guppy mom was in my care for only two days before she gave birth. In all other cases in my experience, males to females ratio has always been very close to 1. However, some guppy strains could be sexed very early, others took a couple of months or even longer.

For guppies of darker colors, I often could see their gravid spots way earlier (as early as one week old) than the difference in anal fins; some light-colored strains had very hard to see gravid spots, but their anal fins begin to change shape after three weeks or so. Some strains took a lot longer to mature. I once put a bunch of young, same-age virgin females of two different strains to breed with one male, got babies of one strain and then discovered that some of the "females" of the other strain were developing gonopodiums 😲.

 

 

[GameCzar]

From our two drops so far, we've only gotten 10 males, with about 20 or so females.   Not sure what that means, if anything.   Never heard of a a drop being all one sex, but I guess it's possible.