Guppy Inbreeding Prevention by Outcrossing

[DustinJWagner]

Hi everyone!

I would like to set up a few single strain guppy display tanks as a part of my fish room with a mix of males and females. I am not interested in selective breeding but rather just desire some pretty tanks for my own enjoyment with occasional fry births.

Of course however, with this type of set up, inbreeding is inevitable and likely to cause issues a few generations in. I don’t really want to dedicate a ton of tanks to the operation. I’m hoping if, for example, I’m running a 20 gallon Red Dragon tank, if I just add a new Red Dragon male every X amount of months with different genes this will suffice. I know the males like to make their way around to lots of females which in theory should diversify the gene pool.

Is this too simple of a solution to inbreeding? How often should a new male be added for this method to work?

thanks 🙂

[PineSong]

In my experience, guppy females have babies every 30 days, the fry take 4-6 months to mature and start producing their own fry. So if you add a new male after a year, you won’t have too many generations of all the same parentage. 
 

[Fonske]

On 4/18/2022 at 5:13 AM, DustinJWagner said:

Of course however, with this type of set up, inbreeding is inevitable and likely to cause issues a few generations in

I have a strain going on for two and a half years, all coming from four siblings (two males and two females, from the same drop). Never outcrossed (tried to get rid of them couple of times actually, i.e. there were population bottlenecks), yet no issues so far, all the guppies are happy and healthy.

I'd say adding a new male (or female) once in a while should be more than enough to widen the gene pool.

[sumplkrum]

As long as you're culling bad fish it shouldn't be much of a problem.

What you don't want is something with a bent back or off-color reproducing. Not selective breeding, but a little bit of population control goes a long way.

A few years down the road you might have to 'freshen up' the gene pool, but that's a long way off.

[Scapexghost]

On a hobbiest level, inbreeding isn't a major concern. Remove individuals with genetic defects, such as bent spines, and you'll have no issue.

[WhitecloudDynasty]

I wouldn't worry about it, a few month won't made a big difference in genetics. Chances are the "new" male you bring in may be the same blood line someone else is working with. 

[nabokovfan87]

Golliad farms has a ton of great information on the topic. I recommend checking out their videos on similar species as well as their blog articles.