Colorful Koi

For one thing, they're beautiful. But interestingly, koi also have personality traits that range from gregarious to, well, coy. In fact, beyond sheer beauty, personality is one of the things breeders look for in prized koi.

Top-quality breeding stock can easily command prices of up to $25,000 per fish; an all-Japanese competition winner went for $1 million. Thankfully, however, you can buy beautiful--if not show quality--koi for just a few dollars. And more and more koi breeders are popping up all over the place, raising fish of varying quality, from average to excellent.

Unless you plan on becoming a koi breeder, you should simply buy whatever fish you like. Butterfly koi--those with long, flowing fins--are among the most popular in the U.S., although they're shunned by a number of experts. And it's okay to be picky, especially since it's a good bet your koi will outlive you. In fact, koi have been known to live as long as 75 years.

You'll need a pond that's at least three feet deep by whatever size you want. And you'll need to pay close attention to the quality of the water.

"The secret to keeping koi fat and happy can be summed up in two words--water quality," says master gardener Paul James. "And thankfully, maintaining good water quality is really quite simple, assuming you've got a good pump and at least one filter, and you take the time to routinely remove leaves, inoculate the water with bacteria and add pond salt."

One thing that can affect water is excessive feeding of the fish, because the food itself, if left uneaten, can foul the water. The more food the fish eat, the greater the accumulation of waste in the water.

Koi will feed in a frenzied fashion, nearly forcing one another right out of the water. But there aren't any hard and fast rules about how best to feed Koi. Some people feed them only once a day, others up to five times a day. Either way, don't use more food than the fish will eat in a few minutes.

Commercial koi foods are readily available, and they offer the fish a balanced diet. But koi also enjoy people food--from watermelon to lettuce to potatoes.

Another thing that can upset water quality is losing water. All ponds lose water due to evaporation, especially during the summer months, so the water must be replaced. If your pond system includes a backwashing mechanism, you'll want to top off the pond each time you backwash.

But adding fresh water to the pond can lead to disaster, especially if you leave the hose running for too long. The problem is that city water is high in chlorine, and chlorine is toxic to koi. So whatever you do, don't walk away from the hose while it's running. And if you should make the mistake that just about everyone has, treat the water quickly with dechlorinating product. A tiny bit of this stuff goes a long way and can make the difference between healthy koi and no koi at all.

Releasing your koi

After 30 minutes, open the plastic bag and let your koi swim out into its new home. Depending on the personality of the new fish--and the reaction of any existing fish to a newcomer--the new guy may be a bit shy or he may begin to frolic with his friends right away. Either way, it doesn't take long for all the koi to get along.

"The sight of several koi swimming together--and playing together--is very cool," says James. "I sometimes sit for hours and watch my koi interact."