Blue-Green Algae Care Guide
Cyanobacteria sp. · Freshwater algae
What Blue-Green Algae look like
Slimy, sheet-like coating in vivid blue-green, dark green, or reddish-purple tones. Forms a cohesive film that peels off surfaces in sheets. Produces a distinctive musty, earthy odor.
Behavior & temperament
Not a true algae but a photosynthetic bacteria. Thrives in low-flow, low-nitrate environments with excess organics in the substrate. Capable of nitrogen fixation, allowing it to grow even in nitrate-depleted conditions.
Behind the name
From Greek 'kyanos' (blue) and 'bakterion' (small rod).
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Blue-Green Algae?
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