Minnow

I was talking with a boy in my art class today, and I found out he has koi! I was pretty excited, since I don't know anyone else who keeps them, so I was naturally curious. He says he has two koi and several mosquitofish in a 55 gallon tank. From what I gathered, the koi are not fully grown yet. I asked him about food, and he says he doesn't feed them, they eat the plants in the tank. Is this normal?

Also, he was talking about his future plans. He said they had a 286 gallon pond (2 wide, 4 long, and 5 feet deep) outside for them when they got bigger, and he also said that he wanted to get a betta and an archerfish to put in there with the koi and mosquitofish. It doesn't seem like there would be enough room for the fish he already has, and I don't think the betta would do well with the others. It seems like a weird combination.

I'd like to try and help him do what's best for the fish. What advice should I give him?

isis

I must say that is a very weird combination!! I'll have to check up on that before I can give you any advice.

Lucy

Some people have had success with betta in a community tank.
However, many others have ended up with hurt or dead fish.
If he wants a betta, I would highly recommend it be in a tank by it's self. A lot of members of the forum have success keeping them with cories, ottos or snails.

I looked up mosquitofish. The info I found said they don't make good community fish.
http://en.wikipedia.org/wiki/Mosquitofish
http://www.fishpondinfo.com/mosq.htm
I also looked up archerfish:
http://en.wikipedia.org/wiki/Archer_fish
Koi's have a different temperature requirement than bettas.

To me, this sounds like a disastrous situation..

Steve113

I'd say his tak will be overstocked anyway, depending on the numbers (you didn't specify)

The betta will be very small in comparison to the koi and is likely to by bullied by them.
Failing that, the betta might nip at the Koi's big fins.

Oh, and the betta would benefit from a heated tank.

sirdarksol

Koi require hundreds of gallons for just one (unless they are butterfly, which tend to be smaller, though they still need a lot of water). Mosquitofish and koi tend to do okay together, because the koi are generally peaceful and mosquitofish aren't big enough to really bother the koi. Aside from that, koi prefer the bottom of the pond, while mosquitofishes' prey sits at the top.
Archerfish and bettas require a very stable temp, while koi and mosquitofish much prefer variable (or temperate) water.

As far as eating the plants, the koi likely aren't getting total nutrition, but there are worse things for koi than lots of fresh plant matter. If the plants are getting lots of light and CO2, they're likely growing fast enough to provide the koi with plenty of calories.

Minnow

Thank you all for your replies. How long can the fish be kept in their current 55 gallon tank? Also, from what I understood, he doesn't feed the mosquitofish either, although I didn't ask specifically. Can mosquitofish eat plants? I thought they were carnivorous.

I'll let him know about the compatability and temperature issues, as well as the size requirements for koi. I don't know whether or not he'll listen, but at least he'll be informed. He seems to really care about them, so I hope he'll do some research on his own. Who knows, maybe he'll find Fishlore!

sirdarksol

Mosquitofish are carnivorous. They eat insects and insect larvae.

There's no set duration on how long they can last in their current tank. The only real answer we can give is: the faster they get a bigger space, the better.

TedsTank

My Koi are all over 24 inches. Butterfly Koi actually grow faster than the standard varieties and with those longer fins they look even bigger. They would be stunted in an aquarium and not get nearly as large. Beware of the Walmart types and most at Petco etc.....they are not high end breeding and many dont have as good breeding and the colors are washed out.(there are excellent breeders here in the states but the fish wont be found in many outlets) I will try to post some pictures this spring....they are dormant now for the winter and it is not good to disturb them.

TedsTank

oh one other thing....the female Koi get the largest. The mails are a bit smaller and more streamlined.

catfishlover123

Um, TedsTank, This thread is really old.