Koi FAQs

We guarantee live delivery and full satisfaction. However, the responsibility for maintaining the health of the fish after delivery has to be shared by the customer. We request that you follow the recommendations listed below:

1. Learn what is required to successfully maintain healthy fish. There are numerous websites available covering all aspects of ponds, filtration, water parameters, koi and goldfish health, etc.

2. Quarantine new arrivals for 2 weeks at a minimum temperature of 75 degrees F. Some fish diseases are not apparent at cooler temperatures. We cannot accept responsibility for conditions created by mixing new fish with existing fish.

By purchasing from our website, the user agrees that Next Day Koi is not to be held responsible for any previously existing fish in a given environment, nor the cost of medications, materials, consultations, or any other costs incurred by the user.

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Well cared for koi will live approximately 25 to 35 years, on average. Some fish will tough it out for considerably longer. A truly exceptional Japanese koi named Hanako lived to the ripe old age of 226 years.

The maximum size for koi is around 3 feet in length and 20 pounds overall weight. But most koi will never reach this truly jumbo size. 20-24” and around 12 pounds in weight is more typical for an average fully grown koi.

There are three main factors in the judging and valuation of koi: body conformation, color, and pattern.

No, this is false. It is possible for Koi and Goldfish to crossbreed, but this is not where Butterfly Koi originated. Butterfly Koi are the result of selective breeding accomplished by Blue Ridge Fish Hatchery. Long-finned carp from Indonesia were crossbred with traditional standard fin koi in order to introduce the long-flowing fins typical of Butterfly Koi today.

Koi are relatively hardy fish, able to withstand a wide range of temperatures. The ideal temperature range for koi is 65 to 75 degrees F. But they will live successfully in water temperatures anywhere from 35 to 85 degrees F.

Most hobbyists feed their koi pellet food specifically tailored to the nutritional needs of koi. Purchase the same koi food that we feed all of our fish.

Koi will try to eat just about anything they can get in their mouth. Many hobbyists supplement their fish’s diets with vegetables, insects, or even dried shrimp.

During the spring and summer, feed your koi twice per day, no more than they can consume in two minutes time. During the fall, feed your koi 2-4 times per week, no more than they can consume in two minutes. During the winter, while water temperatures are 52 degrees or colder, do not feed your koi.

During the summer, koi can easily go two weeks without being fed. They will take some small amount of nutrition from bugs, algae, and anything else they can find in the water to eat.

Koi can go through the entire winter without eating, and should not be fed if the water temperature is 52 degrees or colder.

Yes. Koi are omnivorous, and they love to eat aquatic plants.

Yes, Koi and Goldfish do very well living together. The only time for concern is when very large jumbo koi are placed with very small and fragile goldfish.

The general rule of thumb in the koi hobby is that you should provide 10 gallons of pond or tank water for every 1 inch of koi that you have. However, this ratio can very greatly either way, dependent upon many factors.

Yes. Koi are cold-water fish by nature, and have no problem surviving in a pond through the winter. However, you should take steps to ensure that a) the pond does not freeze over completely b) there is adequate oxygen in the water and c) carbon dioxide can escape from the water.

For bio-security reasons, we never bring koi, other than those from our suppliers, into our facilities. We will never take your unwanted koi.

No, we will not purchase or take any of your koi.

Your koi are most likely spawning. This will occur in spring or early summer, and is triggered by rapid changes in water temperature.

Yes, koi and other aquatic life are adversely affected by chlorine.  Chlorine compromises the gills of fish, making it hard for them to breath.  Chlorine also acts as an oxidizer, removing the protective slime coat of fish and increasing their stress.  If you think you have chlorine (or chloramine) in your water, you can use water conditioners to remove both.

If you have read up on water parameters and other things that koi and goldfish need to thrive, and followed all advice, your fish should live with no problem.  However, there is no way to try other than by adding fish and seeing what happens!  Many people buy inexpensive koi or goldfish from a local store such as Petsmart, and use those fish as “guinea pigs” before adding larger and more expensive fish.

Generally, no.  Koi are coldwater fish, and have no problem wintering over outside.  Koi can even survive in a pond covered with ice, provided that there is adequate oxygen in the water.

Koi owners in extremely cold areas should take precautions to insure that their fish and ponds are prepared for winter.  This can include adding a heater to the pond, increasing aeration in the pond, or possibly bringing the fish inside to a warmer climate.