Hair algae are dreaded by many aquarists and a lot of algae eating animals refuse to eat hair algae in the aquarium. To make things even worse, hair algae tend to show up together with unsightly thread algae.

Hair algae will typically be green-gray or pale green in colour and is known to grow exceptionally fast once it has found its way into a favourable aquarium. If you don’t do anything about the problem, your entire aquarium may be overtaken long green strands of “hair”.

Manually removing hair algae is rarely enough; you need to find out what caused the algae growth in the first place. Some aquarists have reported how green algae began to appear again just a few hours after being manually removed and scrubbed off the aquarium.

In the wild, hair algae have to compete with other plants for nutrients but in an unplanted aquarium where other types of algae are kept in check it can grow exponentially in no time since there is so much food for it to consume. You should therefore keep the levels of nutrients really low when combating hair algae and you may also want to consider introducing live plants that will compete for food with the nasty hair algae.