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HomeProblemsBlack Beard Algae (BBA)

algae

Black Beard Algae (BBA)

A stubborn, dark algae that grows in tufts on plants, decorations, and equipment. Often indicates fluctuating CO₂ levels. Removed by spot-treating with hydrogen peroxide.

Symptoms

Rough black or dark-green tufts and bristles on plant leaves, driftwood, and equipment.
Patches that resist brushing and grow slowly but firmly attached.
Often worst on older leaves and in spots with weaker flow.

Common Causes

Fluctuating or low CO₂ levels in planted tanks are the most commonly cited trigger (E1 excerpt: fluctuating CO₂).
High organic load and low-flow dead spots let tufts establish on surfaces.
Excess light relative to plant health gives algae an advantage over struggling plants — sources weight these factors differently.

What to Check

Check CO₂ stability across the photoperiod and light duration — fluctuations are the leading indicator (E1).
Spot-treat heavy tufts carefully (peroxide spot-treatment per E1 excerpt) and remove badly affected leaves.
Improve flow around affected areas and reduce organic buildup with substrate vacuuming.

What Not to Do

Do not expect removal alone to work while CO₂, light, and organics stay unchanged — tufts return.
Do not spot-treat with peroxide while fish or shrimp are in direct contact with the treated surface.

Recommended

Black Beard Algae (BBA): Causes and How to Get Rid of It

This guide is informational and does not replace professional veterinary advice. If fish are severely ill, consult a veterinarian.