Guppy sex ratio

[Steve2717]

When I first started a couple of months ago my initial purchase was 12 guppies. When I got them home I thought id been screwed as I only saw 11 but then noticed 1 little fry in there too and the LFS mustve counted that one as well. They all appeared to be male (although my brother reckons i may have some alpha females but I dont necessarily trust what he says...he's a clever lad but thinks he knows more than he does). We had a few 4 deaths out of the original crew but the fry stayed with us and now appears full size but never gained colour and pretty sure she's female as she's had loads of fry in the meantime, in fact she's just had a load more. She tends to get hounded by the guys, just wondering what sort of ratio I should have.

 

[lnsaneM]

You can tell the females from the males, the more colourful, bigger tails are males

 

[Steve2717]

Yeah im pretty sure they're all male apart from the 1 female, not sure the sex of any of the fry as they're still too small, theres about 15 of them now at different sizes

 

[nik_n]

What you want is 2-3 females per male. Your ration should be a bitt better now that you got the fry, but you might want to toss in a couple of new females in the tank to keep them from inbreeding

 

[Steve2717]

Thanks thats exactly the kind of answer I was after. Apologies as its late for me but if I have 8 males already with 1 female and 15 fry and say 50% are gonna be female (which is pure guess) that means ill end up with 15 males and 8 females so will need another 22 females to even it up? Jesus im gonna get overrun

 

[nik_n]

Yep that's how it goes with guppies. U might find someone to give these guppies off to, especially if you are planning on getting more females. You will have even more fry then.

 

[emeraldking]

If you're really trying to get more females than males from a batch to ensure the best ratio, it really doesn't matter what the m:f ratio will be when you're dealing with a larger group of guppies. In most cases when you're having guppies of mixed gender, males will get themselves busy with both males and females within the group.

 

[ChasingFish]

Telling males from females is fantastically easy with guppies. The females have dark gravida spots near their vent. Typically the males are more colorful and have longer fins (but some good breeding has resulted in more colorful / long finned females too). I feel very sorry for your ONE female (I know you said you have fry now, so surely you have more females...but if they are not of breeding age yet, the males in the tank WILL NOT LEAVE that one female alone and she will probably not live long with constant harassment and growing and birthing fry). The best ratio in my opinion is 3 female for every male, or keep them separated except when you want them to breed.

 

[ChasingFish]

gravid spot

 

[ChasingFish]

Did you know it takes about 1/20th of a second for the male to "deposit" the sperm?

 

[Steve2717]

Yeah I know about the gravid spot. She was getting beasted and I couldn't bear to watch, she literally couldn't get away. I didnt want to get more fish yet as I wanted a month of stability in the tank first but I had to do something so I threw another 4 ladies in. Ive had even more fry since and now even the new 4 look pregnant. Ive just noticed that some of the older ones are actually swordtails so its replaced the few I lost. There's another Ive noticed but not worked out what it is yet. The guppy fry have no colour but this one is orange/yellow with a black tail...thinking one of my platies has finally had some too

 

[Steve2717]

Did you know it takes about 1/20th of a second for the male to "deposit" the sperm?

You learn something everyday, 1/20th of a second...who said romance was dead

 

[emeraldking]

Did you know it takes about 1/20th of a second for the male to "deposit" the sperm?

This goes for every ovoviviparous livebearer species that the moment of contact is that short to deposit sperm at the front of the female's vent (for it's not inserted by the male). The female herself will suck in the sperm. The sperm will be stored in the folds of the fallopian tube of the female. And when the female decides to fertilize her eggs, she will release sperm by randomly opening one or more folds of the fallopian tube.

 

[emeraldking]

Typically the males are more colorful

Nowadays it can be different with fancy guppies. You've already mentioned that there are even fancy strains where the female has got larger fins. But there are sufficient females these days that are colorful as well.
But there are also fancy guppy strains where males don't have large finnage. There are sufficient fancy guppy strains that are really short finned.

 

[emeraldking]

What you want is 2-3 females per male.

This goes in general for a smaller tank and with a low number of guppies in one tank. When the tank is assumingly bigger or when we're having a large group of guppies, the sex ratio doesn't matter anymore. Then it can be equal numbers of both genders or even less females than males. In a larger tank, the females have more chance to escape from the males. In a large group, males don't only try to chase females but also other males. Just to see who's the dominant male. This will take the pressure of the females.