Aquarium Algae Types

Many forms of algae grow in the aquarium environment and an algal bloom can quickly swamp plants, competing for light and nutrients, until the plants are choked to death. Not only do algae inhibit plant growth, but they also look unsightly and can release dangerous toxins into the water, affecting both plant and fish health. It is impossible to eradicate algae completely, because wherever there is water, light and a minimal supply of nutrients, algae will grow. However, it is possible to keep algae to a minimum, and a little algae growth on rocks and wood may even add to the appeal of a display, as well as providing a source of food for some fish.

In most cases, a well-maintained planted aquarium experiences fewer problems with algae than an unplanted aquarium, despite the additional nutrients. Algal blooms occur in the aquarium only when certain conditions become ideal for algal growth. Fortunately, you can take steps to prevent those conditions from occurring.

Countless types of algae may be present in the aquarium environment, but most are variations on a few groups of common algae. The causes and remedies vary for each type, as does the severity of algal blooming. In many cases, an excess of organic materials and poor water quality or excess nutrients are the main causes of algal growth. An

Red Growth Glass Aquarium

Above: Cleaning the aquarium glass every week, even when it appears clean, can help to prevent the formation of red and other algae. Use an algae pad designed for the aquarium and keep it solely for that purpose.

excess of soluble iron is often a key factor in blooms of "green" algae, such as single-celled or filamentous algae. Some of these algae will suddenly bloom in the aquarium, while others grow slowly but continually.

Single-celled algae As the name suggests, these algae develop as single cells that do not join together or form larger organisms. In the right conditions, these waterborne algal cells can quickly multiply, creating "green water" in the aquarium. Since the individual cells are

Above: Cleaning the aquarium glass every week, even when it appears clean, can help to prevent the formation of red and other algae. Use an algae pad designed for the aquarium and keep it solely for that purpose.

too small to be trapped by conventional mechanical filtration, increased filtration, which is often the first obvious course of action, will not work. Although mostly seen in ponds, single-celled algae blooms can occur in the aquarium and the cause is usually a combination of bright, direct sunlight and a high level of dissolved organic matter. In ponds, UV (ultraviolet) clarifiers are used as part of the filtration system to kill single-celled algae. Although UV light units are available for aquariums, they are not recommended for planted systems because the process can break down some nutrients. The best course of action is to reduce or block any natural sunlight reaching the aquarium and try to reduce the amount of dissolved organic matter. A reduction in the amount of fish feeding and liquid fertilizer dosing, combined with a siphoning or gravel cleaning of the uppermost layer of substrate, should achieve a significant reduction in dissolved organics. If no improvement is seen within a week, a chemical solution may be required.

There are several algae treatments available specifically for single-celled algae. These are often labeled as "green water" treatments. Most of them work by binding the individual algal cells together into larger clumps (a process known as "flocculation"), which can then be taken up by a mechanical filter or siphoned away from the substrate during routine maintenance.

Filamentous algae This is one of the most common aquarium algae and occurs in a number of forms, variously described as thread algae, hair algae, or blanketweed. The algae is produced as long, fibrous, hairlike threads that grow from any surface, usually toward the top of the aquarium and often on the aquarium glass and in areas of water movement. If the conditions are right, this algae will bloom quickly and cover plants and decor, causing many problems within the aquarium. Again, strong light or sunlight, combined with an excess of organic material, may cause this algae to grow. An excess of nutrients or slow plant growth also encourage filamentous algae, among other types, to bloom. Physically remove as much of the algae as possible and gravel clean the top layer of substrate to reduce organics. A temporary reduction in lighting may also help to eradicate the algae. Chemical treatments are available, but use them with caution, as many are harmful to plant life.

Blue-green algae The causes of blue-green algae are not entirely understood, although most occurrences are associated with high nutrient levels, poor water quality, and a lack of water changes. The velvety-looking algae appears as a thin, blue-green blanket across the substrate and/or decor and plant leaves. It is slimy to the touch and breaks up relatively easily. Often, the algae has a distinctive smell, which emanates from the aquarium surface. The algae is toxic as a food source, so algae-eating fish will not go near it. Treatment is not easy; only the most potent algae treatments will have any effect. The algae can be easily siphoned away, but may quickly regrow. A top-layer gravel cleaning and water changes may help to prevent regrowth.

Brown algae Brown algae is the most common type of algae found in aquariums and depending on various parameters, it may grow continually or never at all. The brown-colored algae is not fibrous and forms a covering on any solid objects, most notably, the aquarium glass. Providing any surfaces that show the algae are regularly cleaned, it very rarely causes any problems. Brown algae on the glass can be simply wiped off with a suitable cleaning pad. If there is

Aquarium Algae

Left: Filamentous algae occur in a number of forms. In this case the algae is relatively short, but has spread rapidly to cover the leaves of smaller plants.

Left: Filamentous algae occur in a number of forms. In this case the algae is relatively short, but has spread rapidly to cover the leaves of smaller plants.

Below: Several liquid algae killers are available, but their effectiveness varies and the algae may return after treatments.

How Clean Aquarium Glass From Inside

Left: Algae can build up on the inside of the aquarium glass and become difficult to clear. It is much better to use a scraper regularly to keep the surfaces clean.

Right: Brush algae is slow-growing but difficult to treat and/or prevent. Although it is not harmful, it should be removed to prevent excess growth, which may result in an unsightly bloom and have an adverse effect on the aquarium plants.

Aquarium Brush Algae

causes of algae. If the cause of the algal bloom is not eradicated, the algae will simply grow back after treatment.

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  • veera saikkonen
    How to clean aquarium glass from inside?
    8 years ago
  • gilly
    How to clean fish tank glass?
    8 years ago
  • hyiab
    What is algae plants for aquarium?
    8 years ago
  • mathias
    What does algae look like on aquatic fish tank plants?
    8 years ago
  • ANJA
    How to clean the background of the aquarium glass?
    8 years ago
  • sara
    What kinds of aquarium algae are there?
    7 years ago
  • veli
    Are singlecelled algae plants?
    7 years ago
  • Elisabetta
    Does iron green up aqaurium plants?
    7 years ago
  • corinna
    Can hair algae harm aquarium plants?
    7 years ago
  • luwam
    Does glass top for aquarium harm plant growth?
    1 year ago

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