Species of Chaetomorpha are green algae with fine, unbranched filaments, consisting of large cells arranged in a single row end to end. The filaments are usually stiff or coarse, not collapsing when removed from water. The individual filaments can be straight, curled or twisted and the whole plants can be either clumps of straight filaments, like a clump of grass, or a tangled mat, which in C. linum grows to 1m high and 2m wide. In some species the tangled mats have been compared to tangled fishing line.
This algae is fast growing and is not palatable to many herbivorous species.
Chaetomorpha algae is a renowned species overseas for its ability to remove both phosphate and nitrate from the water. It is favoured over other macro algae for its fast growth, tough qualities, and its failure to undertake sexual reproduction. Sexual reproduction in other macro algae can introduce many pollutants into aquaria, and has been blamed for many tank crashes. The onset of sexual reproduction can be caused by numerous factors, including a sudden change in water parameters or harvesting.
It has a natural distribution range throughout Australia, yet it is under-utilized in Australia in favor of other macroalgae and other nutrient removal techniques.
A cheap, energy saving globe with a low Kelvin rating (5000-6500K) can be used to maximize growth. Cheatomorpha should be 'tumbled' with good water flow to prevent other less-desirable algae from settling on it.