Hair algae
Long green strands on plants, decor and moss.
Fine green strands, from short fuzz to long threads, wrapped around plants, moss and hardscape. Thread algae and staghorn are close relatives.
- Main cause
- More light than the plants can use
- First fix
- Twist strands off with a toothbrush or a rough skewer and siphon them out.
What causes it
- More light than the plants can use
- Nutrients out of balance, often with spare iron or after a fertilizer change
- A new tank before plants have grown in
How to remove it today
- Twist strands off with a toothbrush or a rough skewer and siphon them out.
- Cut the light period and the intensity for a few weeks.
How to stop it coming back
- Match light to the plants and CO₂ you have; more light is not better in a low-tech tank.
- Plant densely with fast growers.
Fish and invertebrates that eat it
They keep it down once the cause is fixed; none of them clears a bloom on its own.