Koi/goldfish offspring - 1st generation - spawning???

[Carla Cowart]

Koi/goldfish offspring - 1st generation - spawning. Will eggs be viable? I've been told that Koi/goldfish mix offspring are sterile but mine are spawning with my true Koi. My very clean pond now looks like it has an oil spill covering the top of the water.

Also, I have fish that are about 4 inches long and they are acting like they are spawning. They may be 2 - 3 years old - at the most! Can they reproduce already? Thanks for the answers.

 

[the loach]

Yes, goldfish can reproduce at that age and size. Though I would advise against crossbreeding goldfish and koi. They are 2 completely different species (goldfish being Crucian carp (Carassius carassius) and Koi Amur carp (Cyprinus rubrofuscus), there is no need for it (both species already have countless varieties) and it will only have unintended and negative consequences.