How can I combat algae in my pond?

Many pond owners dread the thought alone. Algae can become a real plague in a pond. Filamentous algae can clog the system, or floating algae can make it difficult to see a few centimeters into the pond. Some pond owners become so discouraged that they resort to heavy-duty measures. This is a very unwise decision, as will become clear later in this article.

Photosynthesis in Algae

Algae are actually very simple plants that come in many different varieties and sizes. Floating and filamentous algae are the most familiar forms for pond enthusiasts. These algae, like green plants, can produce their food from carbon dioxide and water by converting it, with the help of sunlight, into glucose (which provides the plant with energy) and oxygen (which is a waste product for the plant). This is called photosynthesis.

Nitrates, phosphates and ammonium, the building blocks for algae

In addition, algae use phosphate to build cells nitrates and phosphates . However, algae can also directly absorb ammonium and that is why they often become a pest in the spring. By starting to feed too enthusiastically while the nitrification If the process has not yet started sufficiently, an excess of ammonia will arise in the water, giving algae the opportunity to develop explosively.

Why do I have algae in my pond?

Excessive and therefore bothersome algae blooms can occur in the pond due to a combination of an excess of nutrients (nitrates and phosphates), direct sunlight, a plant-friendly amount of carbon dioxide (between 10 and 40 milligrams per liter) and ammonia.

How do I prevent algae in my pond?

To prevent algae explosions you can take the following measures:

• Provide sufficient water changes to ensure that the nitrates and phosphates are diluted and the algae do not gain the upper hand.
• Feed very sparingly in the spring to avoid an ammonia peak and to give the filter sufficient time to get the colony of nitrifying bacteria back to fighting strength.
• Avoid direct sunlight by using a pergola or shade cloth, for example, to keep the sun out of the pond during the hottest hours of the day.
• A plant filter that enters into food competition with algae.

How do I combat algae in my pond?

If, despite precautions, an algae outbreak does occur, don't tackle it with a product that kills the algae in one fell swoop. After all, algae are Mother Nature's solution in her quest for a healthy balance. Due to the massive algae loss, you can expect an ammonia spike, partly because the algae no longer absorb ammonium, and partly because the death of the algae actually releases extra ammonia. Furthermore, many algae control products are based on heavy metals, which are harmful to fish. These metals can accumulate in the fish's organs, potentially leading to organ failure. Try to tackle an algae outbreak carefully:

• Use a UVC lamp to kill floating algae, but slowly increase the number of hours of operation per day, so that your filter has time to expand the bacterial colony.
• Harvest filamentous algae by removing them from the pond, for example by using a toilet brush Use a cordless drill to remove filamentous algae from the walls. Do this in sections, not all at once.

What is the best remedy against algae in my pond?

In some cases, filamentous algae can become an annual nuisance, despite the aforementioned precautions. Bottom drains can clog with the growth of several meters of algae. In that case, you might consider using a non-harmful algaecide once in the spring. Do this as soon as the filamentous algae starts growing again, not when the filaments are already several meters long. This allows you to use a small dose and prevents ammonia spikes caused by massive algae die-off. An effective and organic product is Active Pond Green Control.

Author: Joop van Tol (www.koitoday.nl)