Koi: Will they grow to the size of the pond?

Hi! Last summer my family built a small pond in our backyard. It's eighteen inches deep, by three feet across, by five feet long. (I think this is about 250 gallons?) Ever since we built it, my parents and siblings have been suggesting we get a/some koi. I read the koi profile and discovered that they need 1000 gallons. My parents say that the koi (like goldfish) will grow to the size of the tank, but I think I remember reading that while that is true, it can harm the fish internally. Is this true? Or am I remembering wrong? If it is true, could you please explain it so that my parents can read it? I would hate to put the koi in a tank too small and hurt them. Thank you for helping me!

 

in too small of an invironment, the fish's skeleton will cease growing while it's organs continue to grow. This will put the fish in horrible pain and eventually end it's life as the organs cease to function from being squished.
no koi should go in that "pond" (here in MN we call that a large puddle).

 

+1. That's an old myth. Kind of like putting a cow in a closet and expecting it to stop growing.

 

Goldfish don't grow to the size of the tank, so to speak... Different breeds have different sizes based on genetics [example; koi can grow over a foot long quickly but ranchus grow to be about 6 inches.] And water quality and food quality and all that sort of thing matters too. And I've have also read / heard that while the outside of a [growth stunted] goldfish looks small, the organs continue to grow and cause serious issues.

While you can't house koi in a pond that small, you could try a species of fancy goldie that doesn't grow as large. Remember that if you get certain fancy goldfish, they'll need to be housed indoors in the winter [if you live somewhere that gets cold winters or snow] since they don't like cold weather. There are plenty of goldfish that look awesome from the top view, like pond viewing, and some are even specially bred to be viewed from the top. A little research goes a long way :]

 

Gemstone, do you have a source for that? My mom would like to read the article if you do. My sister keeps saying that even if our pond is a bit small, it would still be much better than letting them sit in their ten gallon tank at Wal-Mart. Any comments, anyone? My family seems really skeptical; I would really appreciate any more information anyone has, or other sources like articles on the internet. Thanks!

 

I do not have an article on hand, but if you google "stunted growth" it should provide you with plenty.
Any fish's growth can become stunted if kept in cramped conditions, but Goldfish and koi are famous for being subjected to bowls and small ponds. Actually, Iridescent sharks probably have it worse, percentage wise, as do quite a few fish with 4'+ potential.
edit, found some links for you:

 

The calculator down the bottom of the page gives that as 168 gallons.

You could get some gold fish, as an alternative. They will get to a lovely healthy size in that size pond and they can be pretty spectacular too. I have 10 6-8 inch comets in a 400 litre pond and the only problem I have with them is rehousing their babies! My pond is very heavily planted so there is plenty of shelter for the fry.

 

Goldfish (and Koi) give off a hormone into the water that inhibits their growth. When you do water changes, the hormone is diluted in much the same way as nitrates, nitrites, ammonia, etc. If water changes are not done very often, the hormone builds up and slows down the growth of the goldfish (or koi).

Here is an article that talks about the Growth Inhibitor that fish give off.

 

Goldfish (and Koi) give off a hormone into the water that inhibits their growth. When you do water changes, the hormone is diluted in much the same way as nitrates, nitrites, ammonia, etc. If water changes are not done very often, the hormone builds up and slows down the growth of the goldfish (or koi).

Here is an article that talks about the Growth Inhibitor that fish give off.

It seems kinda impratical (in a way) to stop/slow your own growth... It seems like they were expecting to be kept in poor conditions almost o.o

I agree with a few fancy goldfish. You could even do Common Goldfish. They look kinda like koi when they are full grown. Just remember that they like around 30 gallons each

 

It seems kinda impratical (in a way) to stop/slow your own growth... It seems like they were expecting to be kept in poor conditions almost o.o

I think it was developed as a survival thing. Slowing their growth when there are too many in a certain area or during a drought season when the environment could not support additional growth or additional fish. Not that they expect to be kept permanently in poor conditions, but more that they were trying to survive temporary less than ideal conditions. Sort of like how turtles and frogs will bury themselves in mud when their water holes dry up, then emerge when the rainy season starts and refills their ponds.

 

I think it was developed as a survival thing. Slowing their growth when there are too many in a certain area or during a drought season when the environment could not support additional growth or additional fish. Not that they expect to be kept permanently in poor conditions, but more that they were trying to survive temporary less than ideal conditions. Sort of like how turtles and frogs will bury themselves in mud when their water holes dry up, then emerge when the rainy season starts and refills their ponds.

That's why I said "in a way" lol

 

Here's some caresheets I've looked up for you to show your parents hope to not overwhelm them with SO MANY SOURCES agreeing they need about 1,000 gallons......

although this one has a size meant for a small one still good information on the website
-"Koi, like any other animal, have certain needs. If these needs aren't met, your Koi will suffer. The number one thing that can kill a Koi is ignorance. Use these pages to help with keeping your Koi happy, healthy and alive."
https://www.fishlore.com/profiles-koi.htm

Then here's some on stunting animal/fish growth...


Let me know if you want to see more, there were many more websites I just gave a few of the MANY examples.

 

Thank you so much everyone for your replies!!! My mom decided not to get koi She googled Koi and found a website saying they need a deep pond to survive the winter and they need more oxygen than goldfish. She's not inclined to get goldfish as a person at a pet store told us that goldfish are among the dirtiest fish out there. I think we may be getting some rosy reds and some water hyacinth (and maybe some anacharis) for the pond as soon as the stores around here get water hyacinth. I know some people just leave their water out overnight to get the chlorine out of the water before putting it in their fish tanks. Since the pond has been sitting out for a long time, is it safe to assume that the chlorine has evaporated? Thank you so much for your help!

 

I don't think chlorine is as bad for plants as for fish. I think your water should be fine for plants.
What about small cold-water fish, like Cloud minnows? I imagine you could have a small school of them in there for interest and their poo would also help fertilize the plants. I don't know how much oxygen they require, but they would also be easier to winter indoors. just a thought.

 

Thank you so much everyone for your replies!!! My mom decided not to get koi She googled Koi and found a website saying they need a deep pond to survive the winter and they need more oxygen than goldfish. She's not inclined to get goldfish as a person at a pet store told us that goldfish are among the dirtiest fish out there. I think we may be getting some rosy reds and some water hyacinth (and maybe some anacharis) for the pond as soon as the stores around here get water hyacinth. I know some people just leave their water out overnight to get the chlorine out of the water before putting it in their fish tanks. Since the pond has been sitting out for a long time, is it safe to assume that the chlorine has evaporated? Thank you so much for your help!

When you go to buy the fish, you an just take a bit of the water to get it tested. They should tell you what's in it, and what you need to do to it.

 

If your pond is planted, the dirtyness of the gold fish actually acts as fertilizer to your pond plants!

 

Ok, thanks! I read here on FL's profile that rosy reds could be seen swimming under the ice, so I guess I wouldn't have to winter them inside?

 

Ok, thanks! I read here on FL's profile that rosy reds could be seen swimming under the ice, so I guess I wouldn't have to winter them inside?

You will probly have to float a ball or something that can be kicked out of the ice when it starts to get really cold o that there will be an open place for gas exchange durring the winter

 

The koi that she originally wanted are probably even 'dirtier' then goldfish just by the fact that they can grow to 3 times the size. Both are ornamental carp after all

So long as the water doesn't freeze solid they should be fine overwinter. Depending on how cold it gets you might need a deicer or something that agitates the water enough to keep the surface from totally freezing.

 

Well, we have a small fountain (connected to the filter) that keeps the water from completely freezing. This winter, we had an unusually cold spell, but it was only when the electricity went out (rolling blackouts) that the pond completely froze over. Btw, when should I start looking for water hyacinth? I called several plant stores around here and they didn't have any yet.

 

as soon as you want to. you could ask around on Fishlore- you can't be the only person who has a pond and wanted water hyacinth!
Akari, I LOVE your endlers. Can I have a few?

 

Usually the store I work at starts getting those in around mid march to early april. Then we keep them in stock until late fall.

 

Akari, I LOVE your endlers. Can I have a few?

Sadly, I don't have any Endlers. I just got really bored, and happened to have a new trial version of Photoshop Elements 9 on my computer, and google searching skillz lol

If I did have some, though, I would share ^.^