Green Hair Algae (Marine) Care Guide
Bryopsis sp. · Saltwater algae
.Real.webp)
Suggested tank
5+ gal
Diet
Photosynthetic autotroph thriving on elevated phosphates.
Origin
Tropical Oceans Worldwide
Family
Bryopsidaceae
Placement
Live rock (unwanted)
Flow
Any
What Green Hair Algae (Marine) look like
Feathery, fern-like bright green filaments growing 2–10 cm from live rock. More structured and branching than freshwater hair algae. Often grows in dense mats that trap detritus.
Behavior & temperament
Aggressive nuisance algae indicating elevated phosphates and/or nitrates. Extremely persistent — can regrow from microscopic fragments. Traditional algae eaters often refuse it.
Behind the name
From Greek 'bryon' (moss) and 'opsis' (appearance), meaning moss-like.
Plan your tank
Check the numbers before you buy: tank volume, salinity, salt mix, water changes, and your ongoing care routine.
Keeping Green Hair Algae (Marine)?
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