How to remove algae in a pond?

How do you remove algae from a pond? It is one of the most difficult problems to deal with when you are starting a garden pond.

You have just come across this article and you are wondering how to easily remove algae from a pond? We explain everything here!

Algae are a problem for all water surfaces, ponds, lakes, rivers and other bodies of water. But the term "algae" is often used to refer to different plants. It will be necessary to clearly distinguish aquatic plants from algae, which are "gaseous" structures. However, not all aquatic plants are algae. And not all aquatic plants are identical: there are beneficial plants and others that are undesirable and harmful to your pond.

In this article, we will talk about this subject and how to get rid of the algae present and how to prevent their appearance.

What are algae?

Even specialists do not agree on how to call or classify algae. Defining what an alga is is very difficult, but generally speaking, algae are simple organisms that can even consist of one or more cells grouped in colonies and living in an aquatic environment. There are four main types of algae: blue-green algae, filamentous algae, unicellular algae and slimy algae.

Blue-green algae are unicellular (planktonic) and microscopic plants that can grow in any body of water. They can bloom in different colors: bright green, apple green or blood red.

They are the basis of the food chain, and a healthy pond should contain this type of algae as a food source for other living organisms. But excessive growth can turn your pond into a swamp. Blue-green algae have recently been reclassified from the group of algae to that of Monera, which includes bacteria, because blue-green algae are closer to bacteria than other types of algae.

Blue-green algae exist in different colors, for example red, brown or yellow. Blue-green algae are nitrogen-fixing organisms and need nitrogen to live, as well as carbon dioxide, which are very common substances in most ponds. When they bloom, blue-green algae form dense masses on the surface of the pond water and can cover the entire surface.

Filamentous algae are moss-like plants that generally grow in the water or cover the surface of rocks in the water in the form of greenish "mossy" formations. These colonies of united cells have a slimy and mossy texture while the algae attached to the surface have no roots, but have a dense structure. Filamentous algae grow in water with a high content of calcium and phosphorus. Generally, this type of algae comes to life after the addition of lime in ponds to increase fish production. They generally appear in the warm areas of the pond and can grow to cover the entire surface of the water.

Slimy algae are generally slimy, hard or spiky in texture, often causing the most damage when they become a problem for the fish.

Problems caused by algae

In general, the most common complaint about algae is that they harm the aesthetics of the pond. A green pond covered in algae is not pleasant to the eye. When algae cover the surface of the pond, it is not a pleasant sight.

Algae pose a problem for the health of your pond when they are too numerous and when they bloom. During photosynthesis, plants absorb sunlight and carbon dioxide and release oxygen. Photosynthesis is a beneficial process for every pond. Oxygen is necessary for the decomposition of organic matter and for the life of fish and other species living in the pond. However, photosynthesis only takes place in the sunlight. As soon as the sun sets, the plants stop producing oxygen and start consuming it.

Therefore, the more aquatic plants and algae you have in your pond, the more oxygen they produce during the day and the more they absorb at night. The concentration of oxygen in the water decreases considerably during the night. The lowest concentration of oxygen in the water is just before sunrise.

Excessive algae growth also limits the penetration of sunlight into the water of your pond, which can cause a significant thermal stratification of the water. The water that does not receive sunlight and heat cools down and becomes denser. The concentration of oxygen in the water decreases because it is not in contact with the air. This can also reduce the mixing of waters in autumn and spring.

Algae control measures

There are many known ways to control and prevent algae growth. These include herbicides, bio-additives based on beneficial bacteria, chemicals, ultraviolet sterilizers and plant-based supplements such as barley straw. Each treatment acts on the algae in its own way and under different conditions, with different effectiveness. Some products are only effective for a single algae proliferation cycle, while others can be effective for a longer period. Examine the cleaning methods below, with their advantages and disadvantages.

Coloring substances

The use of the water coloring method is an old technology, but it continues to be used and bears fruit. Special powder or liquid paints, blue or black, are used, which darken the water and reduce the penetration of sunlight necessary for algae growth. Enzymes and pond dye are available for this purpose. Another advantage of coloring the water blue or black is that it prevents predatory birds from catching fish in the pond, as it would be harder for them to do so due to impaired vision caused by the color.

But it is not always easy to buy special paints. Furthermore, this treatment method does not work well in ponds designed for irrigation or connected to other bodies of water, because the paints are removed when the water moves. It is also not always acceptable to tint the water of decorative ponds.

Bacteria and enzymes

The application of beneficial bacteria is not a chemical method. It works mainly with living organisms that consume nutrients that would otherwise be available to plants. It is generally a concentrated mixture of bacteria and natural enzymes that quickly break down sludge, improve water quality, reduce suspended solids and eliminate odors.

Bacteria effectively limit lower plants (algae) without damaging higher aquatic plants. In fact, bacteria block the surface of lower algae and it is through the cell membranes of their stems that the metabolism of plants located at the lower level of the surface takes place.