I attached a file here, let's see if it works. My little garden pond has near 100 of a variety and shades of these little buggers, including... blue. One is spectacularly blue and orange. I thought at first they must be koi, but needing to thin the herds out I realized these are NOT 100% koi. I had a variety of goldfish last fill before a winter kill, so who knows... Apparently, they had a little party last year.

One thing for sure, they are not stupid. I caught 3 of them, and the rest, who were very well feed trained, vanished. The brightly colored ones who I wanted the most to catch are going to be interesting to get out. Worst-case I will need to drain down the pond. Best case, I catch 80 more of these guys.

Suggestions? Big old pond lily in the middle in the way.

If they are in fact hybrids, they supposedly cannot reproduce. Instead of getting rid of them, I may be able to put some in the big pond without worry. But I REALLY want to be certain first. I cannot leave them all in the small pond, they won't make it through winter.

Sorry about the low res picture, it was getting dark. I will try to get a better one tomorrow.

liquidsquid,

Had you not led with only koi and goldfish ... I might have suggested the mirror variant of the common carp. Large scales interspersed with scale-less areas are common in that variant. This one looks very similar to examples of the mirror carp fingerlings that I have seen on you-tube. but if mirrors weren't there then I defer to koi or koi/goldfish hybrid.

Not sure what age (dah)/size scales develop on carp and koi but seems like they might start out scale-less and later develop them but still I thought the scales were large and reminiscent of mirrors.

One thing is for certain, like Mules, they inherit the smarts of both parents combined. Where goldfish are relatively easy to catch with a basic net, and Koi are a bit more challenging, these little jerks only had to see one of them get nabbed and nobody will even come for food anymore where they used to rush in for breakfast and dinner. Maybe they will forgive me later when they get hungry. I need to find a larger more transparent net I can lay on the bottom and nab the lot of them during feeding.

The ones I have caught so far are the boring colors, probably only 1/6 of them have some incredible variety of colors.
I have uncaught:
2x Silver-white metallic with black accents.
3x bright yellow-gold metallic with black accents, One of these has very koi-like fins.
1x complete white
2x sunkist metallic orange with speckles
1x Bright orange metallic belly with black back.
1x Dark grey with blue vertical stripes. Yeah, you heard me.
1x Dark grey with blue mottle
1x Orange head, body is light-blue with dark speckles. This one here is a prize fish.

Interesting observations:
The solid colors began to manifest in mid June when I first noticed we had babies. At that time the fish were maybe an inch long. Only 3 or so of the total.
The metallic colors and blues didn't show up until mid July. The darker colors sort of fade away leaving the bright underlying color to become visible.
Some fish are still slowly acquiring color.

There are a few others with obvious colors, but honestly I am shocked at the variety of colors out of a single brood. Most are various shades of subtle hues as in the picture above.

I think the cross is one of the Koi, and one Shubunkin goldfish as I had three of them full-grown last fall. The koi did not seem large enough to breed, but clearly... dang teenagers.

Stayed awake half the night stewing over what I may have to do to get them out so chances of some surviving the winter are higher. Hobbies are the worst.

If they have barbels, one on each side of mouth, they are mostly Koi. The time you are explaining that it takes to color up also sounds like Koi. Carp and Koi are the same fish with differing pigment variations and just like mirror Carp, there are Koi with the same scale characteristics..

Those just might be alien fish,, you see any place around there where a spaceship might have landed?
That being said, we had a little bait pond where we were trying to grow goldfish for river bait as they can be expensive to buy a lot of good sized ones for trotlines and bank poles. they multiplied and grew quickly, exactly as we had anticipated but as you said, were almost impossible to catch with a net, we tried all kinds of tricks, including dropping an umbrella net under water with a hoist system, then feed them above it on a regular bases and then when we needed some quickly hoist the net and were not successful enough to supply baits for us, we wound up completely scrapping the idea and switched to to a different kind of fish to use for bait. some of these that survived the sun perch grew to be 2' long or better.

I don't think the unusually colored fish are hybrids of Koi and goldfish because these fish belong to different technical scientific named genus and individuals from different genera and typically will not successfully interbreed. Technically it gets into number of chromosomes for egg and sperm to combine and form a developing egg. Chromosome number has to be very close in number and similar such as in donkey and horse for the chromosomes to match and for an egg to form and cells to continue division.

They are Std fin koi and Butterfly fin Koi that look a lot more like Goldfish and can crossbreed, which I would suspect is the case as Cody says above.
Squid, I'm an interested buyer if you want to unload them. :-))

The few that I have caught: Some have barbels, some do not.
From what I have been reading, Koi and Goldfish can cross, and it happens often enough to be "common", but they cannot reproduce. If I can confirm they are crosses, some are going in the farm pond. Not going to unless I am certain.

An overcrowded garden pond is sure doom for them in the winter.

I ordered a large koi basket net. I needed to drain down the pond to patch a small hole, and to install an underground line between the basement and pond for air so it doesn't freeze shut in the winter. Any exposed airline gets condensation, and ices closed.

So to continue the mystery, these appear to be from the same brood of fish in the garden pond. I finally managed to catch a few of the brighter ones yesterday as the water is getting colder and they are slowing down. Plus, I left the net under where I feed them, so I finally tricked the littler sneaks.




These are smaller and much more goldfish-like. The iPhone is saturating colors more towareds orange, but the mottled one there is a little on the blue side, but it is subtle.



I stuffed them in my aquarium just to get a better look. I have another in there that is much like the orange and black one, only it is a strange metallic tarnished silver.

Just wanter to point out the dorsal fin on the top fish in the 2nd photo, and the first fish photo's fin. These buggers are just a mishmash of genetics! Pretty cool if you ask me.

What size airline have you had freeze from condensate?

I'd get out as many as you can, especially the different colored ones, then run the aerator in the shallow part of the pond all winter, keeping an open hole. They should be fine..Emphasis on "should be".

Might give Anderson Minnows a call.. Their Black salty is supposedly a cross of Carp (koi) and some type of goldfish.