How can I tell the difference between a very small Koi and Goldfish?

[labs2006]

Hi, just put in our first Koi pond in April this year. We have a couple goldfish, a shubunkin, and butterfly koi. We discovered last night that we have a bunch of little fish of different sizes. The largest baby fish is about an inch long, going from nose to tail.

How can I tell if they are goldfish or koi? Thanks.

[Kittyzee]

I don't have koi, but I do have goldfish.  I believe that koi have barbels on each side of their mouths-one on each side.  I think they use them to find food on the pond bottom.  They look like whiskers--I'm sure on baby fish they would be really small.   

[reddad35]

I am just joking but couldn't resist... here goes.   I wouldn't worry about this until you have a least 2 koi. I would say that since you only have a pair of one fish, they are goldfish.

[ThornyGardener]

It's exciting to find the first babies!

I vote goldies/shubunkin. Reddad35 is correct -- you need 2 to tango.  There are some reports of koi-comet cross, but they are rare and are probably accidental (meaning a pair of goldies were spawning at the same time as a pair of koi and something wafted into the area of the other.) The shubunkin and goldies are the same species and can breed together.

Koi don't usually breed until they are more than a foot long. Goldies do the deed very young and very often (could be every two weeks necessitating ruthless culling).

An early way to tell koi fry from goldie fry: Goldies stay olive/bronze until they are about 1.5-2" and sometimes forever. (I left a couple 3" juvenile sarassa comets in the lily pond last winter, convinced their olive/bronze color was the final color, only to discover they had turned red by spring.) Koi have color as soon as you can see them.

And as stated, koi have barbels (whiskers).

[labs2006]

Thanks for the info. we do have 5 koi in the pond. That's why I wasn't for sure what I had with a couple of gold fish, a shubunkin and the kois. As you say, time will tell, when they get bigger will know for sure. Was just excited to see the little fellers.
Thanks for all that helped.

[trish]

Congratulations on your babies.   

Koi and goldfish do interbreed.  Their offspring (called Mules) aren't exactly on the pretty side and thankfully the offspring are sterile.  A lot of people don't put koi and goldfish in the same pond due to the possibility of interbreeding.

Down at the very bottom of the link is a picture of a Mule.

http://southtexaswgc.org/spawning.htm

[KatFish]

Whoa, that mule is funky looking!