koi fish with stunted growth?

Question

large pond. other fish are ok and normal.this one doesnt grow.appears well and healthy.

Answer 1

PeeTee makes a valid point about getting an older fish that only looked young because it was small/stunted, or just getting a genetic dwarf. Both answers are plausible.

However, I just wanted to add that I have also found that certain colors/types of koi grow faster and end up larger than others. For instance, those breeds of koi that mosty closely resemble their wild carp cousins, like chagoi (copper-colored) and sarugoi (grey-ish), seem to grow faster and end up larger than the "fancier" hybrids. On the other end of the spectrum, the utsuris (single color pattern on a black background) seem to grow slowly and not become as large. The other varieties (such as kohaku, asagi, etc.) seem to fall somewhere in the middle.

Also, females grow larger than males, in general. It is very possible to have a female chagoi and a male utsuri out of the same "hatch" of fry, and have the female be twice as large as the male even though they are the same exact age. Though it is possible that given enough time and perfect habitat, the male could catch up eventually to become more similar in size to the female, it probably won't.

And you wouldn't want any fish to grow too rapidly, anyway - the biggest, fastest growing koi are those most succeptible to scoliosis, or kinking of the spine. Ensuring that your koi have a diet rich in Vitamin C can help prevent this.

Bottom line - if the fish is happy and healthy, there is most likely nothing to worry about.

Hope this helps.

Answer 2

Ive only heard of stunting occur when a fish is housed in a tank that is to small for it. Being in a pond i assume thats not the case. Aside from what pee tee said as being genetic, koi live for a long time and the fish may have been previously housed in a small tank where the stunting occured. Since koi live a long time 80+ years you may have bought an old fish thinking it was a juevenile. Thats my only guess ill pass your question on to people i think can give a better answer.

Addition: i have posted a question about stunting and wondering if there may be other things that can lead to "stunting" other than small aquariums being the direct link to a fishes stunted growth. Ill let you know what i come up with.

Answer 3

OOoooo,Dwarf Koi.
Could be a genetic "sport",could be one that was stunted when you acquired it.
If you could get them to breed true,you just might be on to the first aquarium sized Koi.
That could be very big in Japan.

Answer 4

YES, YOU SHOULD MOVE THE KOI INTO ANOTHER TANK SO HE CAN GROW. BUT IF HE HAS BEEN IN THEIR FOR MORE THAN two WEEKS HE WILL SPROUT UP TO three FEET. THIS IS KNOWN AS KOISPROUTUPITIS. IT WILL EAT EVERYONE. RUNNNNNNNN.