Swordtail Trouble - Over Breeding.

[Michelleuk]

Hi

I started with two swordtails one male and one female. Now I have about 30. The shop told me the fish will eat the young and keep the numbers down.

I didn't relise how quickly the numbers would increase. I brought a new bigger tank to accomodate them all.

Two of the young fish are male and started to chase each other. The older male also does this?

Is there any way that I could keep the numbers down.

I was thinking about rehoming the 3 males, but have read that the females can change into males and also still become pregnant after a few months.

 

[helterskelter]

Females will not turn into males, they are always male, but late developers, most start to sex out at 3 months, but some males will take upto a year.

If you remove the males this will encourage other males to sex out quicker, it's the process of competing with other fish that holds some back longer.

Females will however keep producing fry as they can store sperm for up to 6 months.

 

[theotheragentm]

Separating males from the rest of the tank will eventually stop mating, but it's a tough process as new fry includ males in the batches and those need to be removed as well. Like helterskelter said, it's slow also because the presence of males will slow the development of other males.