Types of Algae

The main groups of algae found in Australian freshwater are:

Macroalgae (Filamentous algae)

Filamentous, also known as “pond moss”, are a common, harmless aquatic plant that tend to grow in shallow, clear lakes and ponds.

It is a thread-like algae that forms dense mats in static water or long, rope-like strands in flowing water.

This form begins growing on the bottom or substrate and then lifts to the surface as buoyancy grows, due to its production of oxygen. It may appear cottony, slimy, or coarse in texture.

These algal accumulations can become unsightly and emit an odour as they decay over time. They can also interfere with swimming, fishing and other recreational activities.

Microalgae (Green & blue-green algae)

Blue-green algae (or cyanobacteria) is often referred to as algae but is actually a type of bacteria.

In some ways they act like plants by using sunlight to manufacture carbohydrates from carbon dioxide and water, a process known as photosynthesis. In doing so, they release oxygen. They grow in dams, rivers, creeks, reservoirs, lakes, and even hot springs.

It is important to know the difference between green and blue-green algae, as blue-green algae can be toxic.

Algae Identification Guide

We’ve listed the main characteristics of some of the most common algae species you are likely to encounter.

Knowing what type of algae you are experiencing can help you determine the best method for dealing with it. Explore our algae identification guide.

Scroll to Top