Went to the pet store to by a goldfish and they sold me a koi..HELP!

[DrDave]

it is a myth that fish will only grow to the size of the tank they are kept in. Their growth will be stunted by the stressed caused by too small a tank, but you don't seem to be the kind to deliberately stress a pet for the sake of convenience. Have you considered a large rubbermaid tub to hold your soon-to-enlarge fish? they are cheap large & sturdy. They don't care if the sidewalls are glass or blue plastic. Actually, the opaque sides might even be less stressful to the fish. Keep it in the basement (but I'm not sure if basements are common in your locale), near the floor drain, just for insurance. Put in an air pump with an airstone, a cheap HOB (Hang On Back) filter, and change 20% of the water once a week. Don't forget to de-chlorinate! Do these few, relatively inexpensive steps and you should be just fine.

It would be helpful if you addressed the member you are commenting to.

 

[Matak]

Ooops. Corrected

... I believe the size of your fish will depend on the size of your fish tank... RDK

. A fishes growth will be stunted by the stress caused by too small a tank, but you (koichallenged) don't seem to be the kind to deliberately stress a pet for the sake of convenience.

I have a 30 gallon tank for two common goldfish. One of my goldfish got sick and passed away a few months ago. My water quality is good and I waited 2 months to make sure my other fish stayed healthy before I got him a new mate. I went to the local fish store and got talked into a Shubunkin, which I found out when I got home and did my research is actually a koi. They had no idea what they were talking about. Now I know koi get very large, but how fast. I think I will need 7-10 months to build an outdoor pond, my koi is currently 3 inches. Will this be enough time?...

Have you considered a large rubbermaid tub to hold your soon-to-enlarge fish? they are cheap large & sturdy. They don't care if the sidewalls are glass or blue plastic. Actually, the opaque sides might even be less stressful to the fish. Keep it in the basement (but I'm not sure if basements are common in your locale), near the floor drain, just for insurance. Put in an air pump with an airstone, a cheap HOB (Hang On Back) filter, and change 20% of the water once a week. Don't forget to de-chlorinate! Do these few, relatively inexpensive steps and you should be just fine.