Color provides a major clue about the pigments the algae uses for photosynthesis:
If you are observing algae in person, these simple characteristics can narrow it down: Easy identification of freshwater algae
: Typically Green Algae ( Chlorophyta ). They contain chlorophyll a and b . Color provides a major clue about the pigments
: Likely Blue-Green Algae ( Cyanobacteria ). They contain phycocyanin. Note: Some like Nostoc form firm, jelly-like "freshwater grapes" attached to rocks. Easy identification of freshwater algae
First, look at how the algae is structured in the water. Most common types fall into these three categories:
: Diatoms often feel gritty (like sand) because of their glass-like silica shells. Identification Resources