Instructions
Place your pond in partial sun. Algae, like any other plant, needs sunshine to grow. If you place your pond in a partially sunny spot you will have healthy water plants while also limiting the amount of light algae can feed on.
Add an abundance of plants because they use nutrients in the pond water and release oxygen. Plants also cover the surface area of a pond to block out light and prevent algae growth.
Buy a UV filter for your pond. While UV filters are somewhat expensive, they are great at preventing algae. Water flows through a channel and is exposed to a UV light bulb which kills algae before the water returns to the pond.
Install proper filtration. Your filter should move approximately half of your pond's water every hour. While koi are not fond of a strong current, moving half of the water in your pond per hour should be suitable to filter the water and keep the koi happy. Biological filters help keep algae at bay and maintain a proper environmental balance.
Supplement your koi pond with products to fight algae. A number of fish-friendly chemicals are available for pond owners to try. Some products kill algae outright and clear up murky water, while others tint the water a deep blue to limit the amount of light available to growing algae.
Depend on your fish to help prevent algae. Koi, a type of carp, eat algae and plants as a natural part of their diet. If you limit the amount of food that you give your koi, they'll naturally clean the bottom and sides of a pond.
How to Stop Koi Pond Algae
Algae is one of the biggest struggles involved when you have a koi pond or other type of water garden. The fight against algae is ongoing and requires diligence, but a few easy steps can help make the process easier.