When it comes to domesticated pets, population control is really easy in breeding, because it is just simple to remove any possibilities in conception until the time has already come to pass for its opportunity. But it's quite different with Koi. They'll always lay and spawn eggs whether you want them to or not, and others will fertilize them as well.

Now, since methods of contraception is not available for them, you may resolve this by removing those unwanted babies after they've been born. As harsh as it may seem, always remember that keeping all the babies that are born can impose danger to both your pond and the parent fish too!

Now, what makes the babies harmful? First, it has something to do with their capacity in size that they could grow into. They will grow up to 3 feet long, and this doesn't matter of what kind of habitat they're being placed into. Now, an overpopulated pond will become a wasteful ones!

Having too many fish will damage a smaller pond, and your pets themselves will be uncomfortable with their habitat. As you set up your pond, have a filtration system for a specific number of fish. Adding extra amounts of fish without adding more system to your pond will produce harmful gases and chemicals that will impose danger to them.

How do you dispose of the babies? There are several ways of doing this. First thing to do is to stop feeding your fish the moment you notice any kind of spawning. Don't worry about them starving, because they tend to focus more on natural foods if they aren't fed regularly.

Now, this "natural diet" also includes their young. Although they're not cannibals, they eat their young when they are still eggs or if they look like little insects, and they would only stop to eat when the time comes that their young looks like real fish. That's why it's quite important for you to start this process as soon as you observe spawning.

Another way of doing this is giving the unwanted offspring away. You can always check your local pet store to see if they have any programs that will accept unwanted animals and give them good shelter. Some stores may even pay a certain amount of money for each fish since they will sell them after (but don't count on this).

Also, you can look for zoos that have this kind of program. If you do know any local Koi society, you can notify them that you have unwanted Koi babies. You can also find an online message board or group wherein you can post your messages and notifications there.

Breeding and keeping your Koi as pets is a fun hobby, but just be sure you take care of them by monitoring their population in your pond regularly.