Koi fish are natural foragers, and over the process of evolution have broadened their diet to include almost anything that they can find in their aqueous surroundings. The breadth of their dining options has helped them to survive, but as they have become living ornaments, the biodiversity in a controlled pond environment is not easily replicated, leaving the owner to match or even exceed the dietary requirements.
The Basics
Most enthusiasts agree that the basis of any koi’s diet should consist of protein, fat, vitamins and minerals. Some carbohydrates and fiber is useful, too, but not as important. There are numerous types of pellet food available on the market, and by doing a little homework, you can suit your koi’s needs to your budget.
Protein
This is the growth part of the diet and one that is plentiful in natural settings. There are different types of protein typically added to koi food, but fish protein (fish meal) and soybean are the most readily digested by fish and ordinarily the preferred method of adding protein. Wheat and corn are additional sources, but first and foremost, fish protein must be in it.
Depending on the season (which is more temperature specific) as well as the size and age of your fish, the percentage of protein required changes. Colder temperatures mean less growth and energy expenditure so the requirements dip too (generally into the 25% range).
Younger fish, however, have more room for growth and are more active so their requirements go up. One-year-old koi will look to get upwards of 40% in their diet while 3-year-old fish will dip down into the 25% region.
Fats
Koi derive a major source of energy from fat and it comprises a fairly large part of a koi’s diet in the wild. Anywhere from 5-10% per daily serving is recommended to give the koi the necessary fatty acids to promote proper energy levels.
Fat is also a key component of delivering vitamins. The amount in food, however, does need to be considered, as high fat foods can promote mold growth and quicker spoiling—meaning more trips to the supermarket or online ordering.
Carbs and Fiber
Not as vital a component of food to koi, it can still provide a ready energy source, but is best limited to about 10% of the daily diet to control starches that can result in liver damage.
Similarly fiber has a tendency to expedite the movement of waste and in doing so hampers the uptake of nutrients. Keeping it around 10% of the daily intake is recommended.
Vitamins
Both varieties (water and fat soluble) in small quantities are an important part of a healthy diet. More specifically, Vitamin K, A, D and E (fat soluble) and C (water), should be part of their balanced diet.
Most food now has this incorporated into it to take the guesswork (and headache) out of it for enthusiasts, but check for it in the ingredients list.
Minerals
Water will provide many of the trace minerals that koi need to retain healthy tissues, but some essential minerals like magnesium (manganous oxide), iron (ferrous carbonate), zinc (oxide and/or sulfate) copper (sulfate) and calcium (iodate and/or carbonate) have to be introduced.
Treats
Or a “supplementary diet,” many enthusiasts will complement their dragon fish’s diet with a number of different foodstuffs to vary their koi’s diet and introduce unprocessed nutrients. Ranging from shrimp to grapefruit, the menu can be fairly extensive.
Other Things to Consider
- If you do buy your food in bulk, cold store your koi food. Refrigerate—don’t freeze—it.
- Food that is furry, smelly, looks a different shade than normal, clumpy or crumbles—toss it. No food is better than bad food. Fish food that is off will cause more problems than not feeding.
- Make sure that the food container is airtight and out of direct sun. Koi food is biodegradable and with both light and air it will decompose quicker.
- Size will make a difference too, as smaller pellets are easier to eat and digest for smaller fish. Larger pellet size usually means that the koi will have to pull it apart once the water saturates it.
- Color-enhancing formulas (like marigold extract, spiraling, and canthaxanthin) can be beneficial in bringing out the vibrant colors of your koi, but genetics and water quality will play a larger part in providing the most colorful foot forward for your jewels.
In addition to having a wide variety of koi fish for sale sourced from some of the industry’s top suppliers, Next Day Koi has a range of koi fish food available to help take the stress out of feeding your koi fish. Available in different pellet sizes and various formulas, the Blue Ridge Fish Hatchery blends will optimize your koi’s health and color.