How to Clean Pond Algae Without Hurting Your Koi

three koi swimming in a pond about to get pond cleaning services done

How to Clean Pond Algae Without Hurting Your Koi

Having a koi pond on your property can be a beautiful addition to your home or business. However, one of the challenges that pond owners face is pond algae. Algae can quickly take over your pond, which not only affects its physical appearance but impacts the overall health of your fish. Today, we are sharing effective methods you can use to clean pond algae without hurting your koi.

Understanding Pond Algae

Algae can easily multiply when the pond has excess nutrients, too much sunlight exposure, and poor water circulation. Excessive algae will eventually deplete oxygen levels in the water, creating an unhealthy environment for koi fish.

Your pond may have filamentous algae, which forms long, stringy strands. Another type of algae is planktonic algae, which gives the water a green or brownish tint.

Prevention Measures

Preventing algae growth in your koi pond begins with you. Keep a regular maintenance routine and set reminders to remove debris, trim nearby plants, and check the pond’s water quality.

Make sure your water filtration system is in good working order, and consider adding plants such as water lilies to combat algae growth naturally. Lastly, overfeeding your fish can increase the nutrient levels in the water, so only give the koi as much food as they need every day.

Manual Removal Methods

If you notice visible algae in your pond, remove it promptly to keep the algae population under control. You can physically remove the algae by gently pulling it out or using algae brushes or rakes. Be mindful and try not to disturb the koi fish while cleaning the pond.

Chemical Treatment Options

While manual removal can be effective, sometimes additional measures are necessary to combat persistent algae problems. There are safe and effective algae treatments available for koi ponds, such as algaecides and herbicides. However, you should contact a fish pond cleaning service provider first. They will know exactly how to tackle your algae problem and tell you what chemical treatment you should use.

Biological Control Methods

Another approach to controlling pond algae is through introducing beneficial bacteria to the pond to consume excess nutrients and inhibit algae growth. Barley straw or extract is another natural and eco-friendly method to control algae. Integrating algae-eating fish or snails, such as plecos or Japanese trapdoor snails, can also keep the algae population in check.

Balancing the Ecosystem

Maintaining a balanced pond ecosystem is essential for the health of your koi. Do what you can to prevent algae outbreaks by regularly monitoring water parameters such as pH, ammonia, and nitrate levels. Ultimately, a proper pond filtration system, adequate water circulation, and strategic placement of shade-providing plants will manage algae growth and maintain the koi pond ecosystem.

Additional Tips and Tricks

Another thing you can do to reduce algae growth is implement sunlight management techniques. These techniques could include adding aquatic plants or installing a pond cover to reduce excessive sunlight exposure.

While these preventive measures and DIY cleaning methods can be effective, dealing with persistent or severe algae issues requires a professional. Hiring a pond cleaning service provider is best because they have specialized equipment to effectively clean your pond and combat algae without causing harm to your koi fish. Additionally, professionals can assess the specific needs of your pond, provide tailored solutions, and offer valuable advice on long-term koi pond maintenance.


Maintaining a clean and algae-free pond will help your koi fish thrive. You can minimize algae growth by implementing preventive measures, such as regular maintenance, nutrient control, and natural algae-fighting methods. However, when you notice persistent algae problems, don’t put it off. Reach out to Aquatic Gardens so we can send a team member out for pond cleaning services as soon as possible.