Baby koi or baby goldfish?

Joined
Aug 19, 2017
Messages
42
Reaction score
10
Location
South Los Angeles, CA
Hardiness Zone
10a or 10b
Country
United States
I inherited a large number of eggs along with some water hyacinth I bought; the pond they were in had both koi and goldfish. The fry now range from 1/4 to 1/2 inches long, although two are much larger than the rest. I have them in a separate baby aquarium.

I only just learned that both types are carnivorous as babies, which now explains why the school of babies went from about 6 dozen to about 3 dozen. :cry::LOL:

To me, they are all indistinguishable at this size—they are all transparent (I can see their internal organs) and basically colorless. When will they start to look different enough to tell what they are? The pond I have has shubunkins and mosquito fish.
 
Last edited:

Jhn

Joined
Jul 3, 2017
Messages
2,213
Reaction score
2,254
Location
Maryland
Showcase(s):
1
Hardiness Zone
7b
Country
United States
Koi have barbels and a downturned mouth for bottom grazing, while comets have a straight on mouth for midwater feeding.
 
Joined
Aug 19, 2017
Messages
42
Reaction score
10
Location
South Los Angeles, CA
Hardiness Zone
10a or 10b
Country
United States
Koi have barbels and a downturned mouth for bottom grazing, while comets have a straight on mouth for midwater feeding.
Thank you, jhn—I do know how to tell them apart as adults. But how large will they have to be/how long will it take until those distinguishing features become apparent.
 

Jhn

Joined
Jul 3, 2017
Messages
2,213
Reaction score
2,254
Location
Maryland
Showcase(s):
1
Hardiness Zone
7b
Country
United States
Good question, never paid that close attention, to see when you can tell the difference.
 
Joined
Aug 19, 2017
Messages
42
Reaction score
10
Location
South Los Angeles, CA
Hardiness Zone
10a or 10b
Country
United States
It shouldn't be too long but the problem is that koi and goldfish will breed and the offspring are hybrids and are usually sterile.
Thank you—that hadn’t even occurred to me! By saying “not too long,” is there any idea of what that could be? Six months? A year? Or how large they have to be before they start to color up and display characteristics of koi vs goldfish?
 

Mmathis

TurtleMommy
Joined
Apr 28, 2011
Messages
13,893
Reaction score
8,087
Location
NW Louisiana -- zone 8b
Hardiness Zone
8b
Country
United States
OK, been doing some research on baby koi/goldfish. Too many articles to reference (but there is a lot of info out there). These are “in general” distinctions, as all fish are going to be different. Please don’t jump on me! Not saying these are “gospel,” just what I picked up after a Google search — we all know that MOTHER NATURE does what she want, so……..

  • KOI: Barbels show up after about 2 weeks of age (IOW, unless you know WHEN they were hatched, you won’t know how old they are). These are temporary and will (supposedly) disappear after a few months, before the permanent barbels grow out (never knew that about koi!).
  • KOI: Most are hatched with some of their color showing.
  • KOI: grow rapidly (maybe faster than GF, but I didn’t see that comparison in writing — just that they grow rapidly)
  • GOLDFISH: are usually olive-colored or black when hatched, and gradually change color — some will stay black for a few seasons.
  • KOI: unless specifically bread with these genetics, baby koi are rarely hatched as black
  • KOI/GOLDFISH HYBRIDS: these have been classified as “ugly” — take that as you like
  • KOI/GOLDFISH: body shapes differ.
My only experience with fry was when I had fry in my pond and was trying to distinguish baby GF from minnows. At that time, I got really good at picking out which was which (mainly by looking at body shape and schooling patterns). Then, my focus went to distinguishing the plain GF fry from Shubunkin fry. Apparently back in those days I didn’t have anything better to do than put baby fish in my 20gal and spend hours observing and taking pics of them for comparisons.
 
Joined
Dec 16, 2017
Messages
13,384
Reaction score
10,486
Location
Ct
Showcase(s):
1
Hardiness Zone
6b
Country
United States
KOI CAN BE DULL for over a year then all of a sudden can start coloring up . often most are olive and then at about a year they start showing their patterns and color
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Similar Threads

Wanted baby Koi in Long Island, NY 0
New Baby Koi 1
Baby Koi 4
Baby koi? 10
Petsmart baby koi keep dying 26
Found a baby koi! 16
how to start a pond with 2 baby koi? 20
Baby koi bumps or spots? 9

Members online

Forum statistics

Threads
30,782
Messages
508,589
Members
13,042
Latest member
lucaryan

Latest Threads

Top