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What Is Pond Algae and What Causes It?

What is Pond Algae and What Causes It

Algae is a common issue that arises in all ponds from time to time. Its unsightly and often has us frustrated with our ponds.

If you see algae forming in your pond, don't panic! Algae is a normal part of any organic ecosystem. If there is a small amount of algae, it's completely fine; it's when it grows excessively that it may become difficult to manage.

In this article we'll go over what algae is and what causes it. This information will help treat and prevent it from being an issue in the future.

What are Algae?

Algae are a primitive (predominantly aquatic) organisms often found in bodies of water with water quality issues. Their photosynthetic pigments are more varied than plants and their cells have features that are not found in plants and animals. Algae are oxygen producers however they can also remove oxygen from water. They combine carbon dioxide and water to form sugars for energy and growth. When sunlight is not available at night they quickly respire, which uses stored sugars and oxygen to form carbon dioxide, which in turn depletes the oxygen in the pond causing further issues. Algae play an important role on earth as a food source for most aquatic life, they are also used as a source of crude oil and used for some pharmaceutical and industrial applications.

The Two Main Types of Pond Algae

There are 2 main types of algae found in ponds. 1. Filamentous String Algae which forms clusters of hair-like algae that attaches to rocks, plants and other surfaces and 2. Green Water - Suspended Pond Algae which floats in the water causing water to look cloudy and green.

1. Filamentous Algae

Other Common Names: String Algae, Hair Algae, Carpet Algae, Spirogyra, Water Silk

Description: Long, thin, hair-like strands of algae. Together, these strands can form thick mats. They anchor to rocks and other surfaces before floating to the water surface. This algae can grow quickly and impact the appearance and health of a pond. This algae causes no major issues in small quantities. It should be kept under control.

Toxic: No

String Algae - Hair Algae

2. Green Pond Algae

Other Common Names: Pea Soup Algae, Green Water Algae, Suspended Algae, Chlamydomonas, Chlorella, Closterium

Description: One of the most common algae's; these free floating algae are microscopic and give the water a green colour and cloudy appearance. It forms around the bottom, edges and surface of ponds and is visible during blooms.

Toxic: No