Care of Koi Pond Fish

Prepare the pond before introducing the koi. Keep in mind that koi require a pond that is between 3 and 5 feet deep and large enough to contain at least 1,000 gallons of water. You will also need a pond filtration system that is capable of keeping the water flowing and properly oxygenated for your koi. The size and type of filtration system will depend on your pond setup and dimensions.

Stabilize the pond water before adding koi. Koi require water with a pH between 7.0 and 7.8. The water should not have any nitrites or ammonia. These levels will need testing at least once a week with a pond water testing kit. Stabilization of nitrites, ammonia and pH is accomplished by following the instructions on the pond water testing kit.

Determine how many koi you can fit in your pond before the purchase. Each koi will need at least 10 square feet of water. So if your pond is 100 square feet, it can handle a maximum of 10 koi.

Feed the koi two to four times a day during the warmer months that average between 60 and 85 degrees Fahrenheit. A thermometer in the pond will help determine water temperature. The metabolism of koi is faster in the warmer months than in the cooler ones, so the fish are more active and get hungry faster. A high-protein koi food is best during this time. If the temperatures rise above the 85 degree Fahrenheit mark and average closer to 90 degrees Fahrenheit, discontinue feeding until the temperatures drop back down.

Cut down on feeding once the water temperature falls below 60 degrees Fahrenheit. For instance, if you are feeding the koi four times a day, only feed them twice. Offer the koi low-protein, cold-weather food at this time. Stop feedings altogether when the water temperature reaches 50 degrees Fahrenheit.

Install a bubbler and pond de-icer if you live in a climate that experiences cold winters. Both will prevent ice from forming on top of the pond. A de-icer set at 34 degrees Fahrenheit will ensure that the pond water remains at a safe temperature level for the koi, which is usually around 40 degrees Fahrenheit. Too much ice forming on top of the pond limits oxygen in the water, eventually suffocating the koi.