Koi Pond Algae
Posted in Koi care, Koi Garden, Koi pond on 07/11/2010 06:53 pm by KarlaGet Rid Of Koi Pond Algae!
With all the hot weather coming so early this year lots of us are experiencing some problems with algae in our ponds.
The best thing to do is to not let things get out of control. Like most problems, nipping koi pond algae in the bud is much easier than trying to deal with it when it starts to take over your pond!

String Algae
The biggest causes of algae are too many koi (thus producing too much fish waste…algae’s favorite food) and overfeeding your koi (once again producing too much fish waste, as well as decomposing organic matter, another favorite food for algae).
Some of the best ways to minimize algae, since a little algae is actually beneficial to your pond are:
- Keep your pond well aerated, especially down near the bottom where debris tends to collect, by using some air stones.
- Make sure the size of your filter is adequate for the size of your pond and that it offers both mechanical and biological filtration.
- Using a UV light during the warmer months helps to keep your pond water clear and control algae.
- Pond plants, a big favorite of mine, can provide shade (many experts recommend 50-75% of your pond being covered with floating plants such as water hyacinth, water lilies or water lettuce) and submerged plants help oxygenate the pond as well as competing with the algae for nutrients.
- Adding beneficial bacteria to your pond also helps keep algae at bay. Most suppliers sell microbial bacteria that you can add to your pond.
One thing I recommend staying away from are algaecides (chemical algae killers) unless you don’t have fish or plants in your pond….these products can kill off your beautiful pond life!
You can learn more about proper koi pond care in my manual “Koi Care Basics”.