Male to female ratio

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dmolavi

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Sexing Swordtails and Male to female ratio

I have 2 koi swordtails in one of my tanks, and despite the assurance of the LFS that they were a M/F pair, they are both males. They're not bothering each other, but I want to get a female in the mix. Should I get 2 females, one for each?

Is there a sure-fire way to sex juveniles, before the sword has developed on the male?
 
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What size is the tank? Ideally you need to have 2-3 females per male. If they had 1 female each, they would be harassed by the males and could potentially die.
 
Hello dm...

For "Livebearers" 4 to 5 females per male is best. This will give all the females plenty of rest between the times they're trying to get away from the male.

Get some Anacharis and Pennywort floating in the tank too. The more plants the better. Makes the fish feel more at home and provides good hiding places.

I hope you have a fairly large tank. Livebearers reproduce about every 28 days in good water conditions.

B
 
The 1:2 male:female ratio is pretty common but not fool proof.

I had a 2:2 ratio and the dominant male still harassed the sub male even though he hardly ever came near the females.

So while not all ways the case it's entirely possible for your males to get along just fine even with the addition of females to the tank.

As far as sexing goes its not always easy. At 1-2 months male juvies will start to mimic adults and flare fins and chase each other. At 3-4 months they will start to develop the gonopodium before the sword.

Also it's important to know that some males will not develop sexual characteristics( no gonopodium or sword ) for several months in the presence of another dominant male in the tank. It's a survival strategy and I've been fooled before by this also.

Some male swords will also not get along with male platies. I had a red wag male that did not get along with a male sunset wag. But I also have a green sword male that pays the same( variety )platy no mind at all. Maybe similar color had an influence. I haven't tested it further.

I've raised quite a few batches of swordtails and one batch of platies so I had front row seat to all my observations.

My current ratio is 1:1 and while not optimal, the male I have isn't as aggressive as was his brother and the female pretty much tolerates him easily enough.

So pretty much it depends on the aggressiveness of the male(s) which can be determined through observation.
 
Hello dm...

For "Livebearers" 4 to 5 females per male is best. This will give all the females plenty of rest between the times they're trying to get away from the male.

Get some Anacharis and Pennywort floating in the tank too. The more plants the better. Makes the fish feel more at home and provides good hiding places.

I hope you have a fairly large tank. Livebearers reproduce about every 28 days in good water conditions.

B

Its a 56 gallon tank. The two males completely ignore each other.

I'm going to see if I can get 2 females (confirmed females) this week for them. I'm not looking to breed intentionally, but i love their color and would like more of it in the tank.
 
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