Stopping Koi Pond Algae

Stop Koi Pond Algae

The growth of algae in your Koi pond is definitely not a good sight to be seen and moreover, it also provides a bad odor to the surrounding environment. If algae are not removed from the pond, it will somehow produce ammonia and if your Koi pond has excessive ammonia, it will reduce the oxygen supply thus threatening the lives of your fishes.

What you need:

  1. To restrict the amount of direct sunlight
  2. Add plenty of plants in the pond
  3. Use UV filters
  4. Installing proper filtration
  5. Use supplement products to fight algae


  1. The Koi pond needs to be placed in an area with partial sunlight because algae need sunshine for its growth. Placing the Koi pond in a partially shaded area will provide you with healthy water plants plus also limiting the amount of sunlight that can help the algae to feed on.
  2. You can add plenty of plants in the pond to enable the usage of nutrients in the pond water and releasing oxygen. By doing this, the plants also help to cover the surface of the Koi pond and blocking sunlight from coming through and also preventing the growth of algae.
  3. If you have the budget, you can also use the UV filter for your Koi pond. It may be expensive but it is a great solution in preventing algae growth. The UV filter works whenever the pond\’s water flows through a channel and is exposed to the UV light, it will kill off the algae before the water returns back to the pond.

  4. You will need to install UV sterilisers if you have green water. You should however remember that you should not rely solely on the UV unit to get rid of algae in the water. The filter that you\’ve installed should be sufficient to solve the green water problem.
  5. The filtration system that you installed should move approximately half of the pond\’s water every hour. Although the Koi fishes are not fond of strong currents, making half of the water in your pond per hour should be sufficient enough to filter the water. Using biological filters help prevent algae growth and also maintain environmental balance properly.
  6. Supplement fish-friendly products can also be used in fighting algae for example; some of the products in the market will kill the algae automatically when they are used and also clean all the murky water inside the pond. There are also supplements that can only tint the pond\’s water into deep blue in order to limit the amount of sunlight from penetrating into the water thus preventing algae\’s growth.
  7. You can also depend on the Koi fish to help you prevent algae\’s growth because Koi fish eats algae and other plants as a natural part of their diet. If you reduce the amount of food given, the Koi fish will definitely clean the bottom and also the sides of your pond.

By now, you must have successfully stopped and ended your Koi Pond algae.

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Additional Reading:

The Guide to Owning Koi

Raising Healthy Koi Secrets