Freshwater Algae | Easy Identification Of
: Often Diatoms . They contain fucoxanthin and have silica in their cell walls, making them look like tiny shards of glass under a microscope. 3. Use Quick Field Tests
: 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
: Sites like the NIWA Algae ID Guide and the Landcare Research Guide provide visual references for different habits. : Often Diatoms
: If you can pick up the algae with a stick and it hangs like hair, it is likely a filamentous green alga. If it is slimy and slips off immediately, it may be cyanobacteria . Use Quick Field Tests : Likely Blue-Green Algae
: Fresh blooms often smell like freshly mowed grass; older, decaying blooms may smell like rotting garbage.
First, look at how the algae is structured in the water. Most common types fall into these three categories:
: These are large and "plant-like" but lack true roots and leaves.

