Algae, Cyanobacteria, other bacteria and viruses

Algae is a photosynthetic plant that grows in water. Macroalgae are large and complex (e.g. seaweed). Microalgae are microscopic and simple, with each individual plant – or cell – being invisible to the naked eye. Microalgae can be found in rivers, dams, lakes, waterways, and oceans. While individual cells can't be seen with the naked eye, together microalgae can grow and group together, turning the water it lives and grows in shades of green, red, and gold. In some cases, this microalgae can be bio-luminescent. (https://www.uts.edu.au/climate-change-cluster/our-research/deep-green-biotech-hub/education-and-outreach/what-algae)

Cyanobacteria (blue-green algae) are a type of microscopic, algae-like bacteria which inhabit freshwater, coastal and marine waters. Cyanobacteria photosynthesise like plants and have similar requirements for sunlight, nutrients and carbon dioxide to grow and produce oxygen. There are many different varieties of cyanobacteria. While often a green or blue-green colour, they can also be white, brown, blue, yellow-brown, or red. (https://www.waterquality.gov.au/issues/blue-green-algae)