Algae guide
Hair Algae in Aquarium: Why It Grows and How to Remove It
Last updated: May 2026
Quick summary
- What it is: Thread-like green macroalgae tangling mosses and branching stems resembling wet cotton candy.
- Severity: 2–3 / 4 — Moderate—can engulf moss beds if unattended
- Primary cause: Light/nutrient/CO2 triangle imbalance—typically excess illumination versus carbon availability.
- Primary fix: Manual harvest marathons paired with disciplined photoperiod trim, algae-eating fauna, disciplined macro dosing—not blind nitrate starvation.
Biological infantry
Larger Amano shrimp shear tufts aggressively; juvenile Florida flagfish nip fine threads cautiously amid warm water mandates.
Photoperiod austerity
Slice noon peak-par by 35% weekly until growth velocity dulls rather than blackout-shocking prized stems.
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