You have taken great time and expense to build your Koi pond. You have taken even more time in selecting and stocking your Koi fish. All of these great efforts will be in vain if you do not adhere to proper Koi pond maintenance. Such maintenance involves all aspects of your pond's condition; from controlling algae in ponds to oxygen levels and water changes.
Your Koi pond maintenance should start with controlling algae in ponds. This is achieved by ensuring that at least 60% of the surface area of your pond is covered in shade. Algae need sun to propagate. Deny them direct sunlight and you will have a stronger hand in controlling algae in ponds. Of course, providing weekly routine maintenance to your pond's filtration system will also go a long way in this regard. Checking the filter, ensuring that the pumps are working properly and checking UV bulbs will not only keep algae under control, but also keep water chemistry within acceptable parameters.
Purchasing a siphon pump for your pond is another way to facilitate Koi pond maintenance. Using the siphon pump monthly to drain 10% of the water and debris which has accumulated in the bottom of the pond will lighten the load on your filtration system and keep your water chemistry in check. During this time, you can also use pond scrubbers to clean rocks, substrate surfaces and other areas that display algae outbreaks. When replenishing the water that was removed, make certain to do so only with dechlorinated water. Chlorine can be hazardous, even deadly, to your Koi.
There are also special seasonal chores associated with Koi pond maintenance. During the fall, leaves will have a tendency to fall into your pond. These should be removed as soon as possible. Otherwise you run the risk of having them decompose and contaminate your Koi's habitat.
Just before the first chill of winter hits, make certain that you have properly completed your weekly and monthly maintenance routines for that time period. Before your Koi enter their dormant/hibernation period over winter, it is imperative that water conditions in your pond be at optimum levels. Check pH, oxygen, nitrate and other chemical levels right before this period.
During winter, monitor severely low temperatures carefully. Koi are hearty fish and by nature will enter a dormant stage when the temperatures drop. Even so, if water temperatures drop below 45 degrees Fahrenheit, especially if they as such for multiple days, you may want to consider using a water heater or else relocate the Koi indoors. The latter option should be done only as a last resort.
Spring is a good time to conduct a full systems check of your filtration system. This will be around the same time that your Koi will begin to exit their dormant stage.
As the summer months roll in, especially in hotter climates, water evaporation is something hat must be kept an eye on. If water levels drop, this can lower the amount of oxygen available to your fish and also concentrate a build up of dangerous chemical imbalances in the water. During the hotter months water replenishment may be done as often as on a weekly basis.
Keeping up with weekly, monthly and seasonal Koi pond maintenance is the best way to keep your pond and your fish at their peak. Besides, most of the maintenance routines can actually be done in such a way that they become an enjoyable way of interacting with your Koi and pond. This is very similar to the pleasure and relaxation that gardeners feel when they work on their gardens.