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The Life of Koi: Understanding The Upkeep of Koi Ponds And Water Gardens

Chapter V: Natural Solutions to Getting Rid of Algae

There are more natural ways to keep the algae out the pond that won’t hurt the fish or plants. Once you algae is under control, a few maintenance changes will help keep the algae at bay.

If you have stubborn algae you may need to remove your fish and power wash your pond. In addition to using Rescue Rock and Waterfall Scrubber to control algae, you can also add barley straw to the pond. Use .025 pounds of straw per square yard of surface area. Simply place the straw in a mesh bag with a rock weight, and place the bag in the pond and let it sink to the bottom. As the straw decomposes, it releases a chemical that controls algae. It works best if added in the spring before algae become overwhelming.

Another way to control algae is to use fountains. Fountains can add beauty to your pond, but agitate the water enough so that algae won’t grow. It depends on the horse power and series.

Reduce the amount of food you feed your fish. Only give enough food for the fish to consume in five minutes.

Reduce the amount you are feeding your fish. Feed your fish only what they will eat in five minutes. This will reduce your nitrogen load and lower the amount of food that ends up on the bottom of your pond. Hungry Koi will eat hair algae, however, it isn’t nutritious, so don’t use this as a main food source for you Koi.

Keep a skimmer handy. Remove debris that falls on the pond surface before it sinks to the bottom to decompose. Depriving the algae of the extra nutrients keeps it from growing.

 Keeping a skimmer handy removes debris that falls into the pond before it sinks to the bottom and decomposes. Depriving algae nutrients keeps it from growing.

Adding plants to your pond and around your pond will compete with the algae from getting nutrients. They also add more shade to your pond. Small plants, trees and shrubs add beauty to your pond. Algae needs sunlight to grow, the less sunlight available, the less algae can grow.

Another way of keeping algae from getting too bad is adding Plecostomus aka plecos, aka algae eaters, aka sucker fish to your ponds. Plecos are usually found in aquariums and are tropical fish, but they can be beneficial in Koi ponds. It is highly recommended that if you decide to add plecos to your pond that you add them during the summer. In the winter, they need to be housed in a aquarium. 50 degrees is the lowest temperature they can be exposed to. Don’t expect to see them much if you put them in your pond. They are a hardy fish that will help clean the algae off the rock and bottom of your pond.

 plecos are a good and inexpensive way to control algae in your pond.

If you decide to get a pleco for your pond it is highly recommended you get a common pleco. There are species are inexpensive. They can get up to two feet long and can live up to 20-30 years. These fish are beneficial to your pond because they not only eat the algae, but they also eat other debris, such as fish carcasses and feces. If you are going to have plecos in your pond be careful because they can aggressive towards the same species. Be careful because occasionally a pleco will attack your fish and eat the slime coat off them and badly injury them or even kill them.

They can get good size outside, sometimes growing a foot in one summer, moving them in and out isn’t that easy. They can get two feet long. If you to decide to get a pleco for your pond be sure to have a big enough aquarium for them to winter in.

The most permanent solution is to use a UV light. UV light sterilizes that algae so that it cannot produce. Sterilizers create healthy, clear pond environment for Koi fish by eliminating free floating organic materials.

Using a skimmer will remove floating material before it has a chance to sink and lessen the chance of decaying, thus changing the water quality parameters and becoming a source of nutrition for algae.

Should a string algae bloom occur, just clean your skimmer often, so that the skimmer doesn’t become clogged.

Adding calcium bentonite helps control string algae. There are many theories as to why this helps—from creating a healthier bio systems in the waters and your koi’s digestion system to smothering algae. It can cloud your pond for a few days.