What is aquarium algae?

Contrary to what most people think, algae are not part of the plant kingdom. They have their own specific classification. Algae are cells that have special components called "chloroplasts". The chloroplast is the part of plants and even algae that can carry out photosynthesis, a process in which food or nutrients are produced by catalysing light.

The difference between plants and algae is this: algae do not have the systematic components found in plants: they are leaves, stems, root system, etc.

Algae exist in different structures. Some appear as dust settling in the aquarium, while others form thin blankets on the water surfaces. Other forms are filamentous, existing in the form of threads. Algae can also (in their nastiest version) exist as slime - this species will completely destroy the aquatic beauty of your aquarium. Algae may also form partially transparent films on the water surface. This is why it is important to do something about it as soon as possible before algae take over the entire aquarium.

Causes and effects

Algae thrive in aquatic or humid conditions. In addition to these basic conditions, if you add fertilizer, the algae will multiply! These include phosphates, nitrates and sulphates. This means that if you add water which comes into contact with leached minerals, it will result in an even greater algae infestation.

Algae can spread due to the use of contaminated water sources. Examples are water from open bodies of water such as rivers. So, if you do not take care of your water source, algae in your aquarium will not last long.

Overfeeding the fish is another reason for algae. If the fish are constantly overfed, food remainders may give rise to rapid growth of algae. Algae may also be caused by prolonged exposure to bright light. Light is decisive for photosynthesis. If the light intensity is high, the algae grows faster.

For most fish, algae are harmless when kept in the aquarium within reasonable limits. Species such as goldfish particularly like to eat them. However, large quantities may cause problems for the aquarist. The aquariums become unattractive and the inhabitants will be miserable to look at.

Algae grow aerobically and consume oxygen at night. This is bad enough, because the fish also need oxygen. This can lead to premature death of aquatic organisms due to lack of oxygen.
As algae multiply, it can form a blanket on the surface of the water. These blankets may be thick enough to block proper air exchange in the aquarium, which may lead to suffocation in the fish.

Common types of aquarium algae

Algae come in different shapes and colours. Below are a few common examples.

String algae

Have you ever heard of string algae? They are also known as string algae. String algae exist in the form of strands usually green in colour (with various shades). The texture varies from coarse to finer and even slimy. String algae attach themselves to organisms that move in the body of water, thus spreading, taking over more and more territory.

Green algae

Green algae come from the same kind of cells that can float easily in water. This means that they have the ability to spread fairly quickly. This form of algae thrives in well-lit places.

Dinoflagellate algae

This type of algae is also known for its ability to form layers. They produce a brown slime which can sometimes be beneficial to aquatic life. Note also that not all dinoflagellates undergo photosynthesis. This tends to reduce their harm to aquatic life.

Black algae

You may know the legend of the slimy pirate Blackbeard - there are algae with the same name. Black Beard algae are unique because of their dense cluster of fibres. The threads protrude from a single source. This type of algae grows on the surface and sometimes on the leaves of plants. They can exist in other shades, such as grey. This type of algae is easier to deal with physically, using methods such as scraping.

Brown algae

This is a fun group of algae, and here's why. They appear in new aquariums and disappear instantly. This is because this species is found more often in large bodies of water, such as lakes. They cover the surface of the aquarium with a brownish patina. Most aquarists will notice the development of these algae a few days after starting a new aquarium. If they do occur, be patient, and they will disappear within a few days once the aquarium is biologically balanced.

Green dust algae

This group of algae is particularly annoying. They form green dust that settles on the surface. This dust may cause irritation in aquarium fish.

Cladophora

This type of algae is a real weed. If there are stones or similar surfaces in the aquarium, this old-timer will be the first to take up residence. Cladophora germinates mainly on hard surfaces. This species is usually green in colour.

Preventative measures

Controlling algae depends on the species. However, there are general methods that will help you deal with it:

• Systematically change the water in the aquarium with fresh water;
• Limit the light intensity, as algae multiply rapidly in bright light;
• Use algaecides. However, be careful when using them. Apply them exactly as instructed - no more, no less. In addition to algaecides, other plants can also be used to combat algae. These plants compete with algae for resources, which in turn controls the algae population;
• Some types of algae can be physically scraped off. However, this may prove to be quite a tedious task;
• Avoid overfeeding your fish. Uneaten food triggers an algae growth;
• Fish that feed on algae, such as goldfish, may be introduced.