Chaeto Algae care guide
Chaeto Algae (Chaetomorpha linum) — high light, 22-28 °C, pH 8-8.4, no CO2.
Compiled by Aquairi from published sources · Published · Updated
Overview
Chaeto Algae (Chaetomorpha linum) is an aquatic plant of the family Cladophoraceae, listed in the Aquairi knowledge base as a beginner-level species. It is typically grown under high light and without obligatory CO2 injection on any substrate. Tangle of stiff filamentous green macroalgae used in saltwater refugiums to export nitrate and phosphate. Grows in clumps under refugium light; harvest regularly to keep nutrient export active.
Taxonomy
- Family: Cladophoraceae
- Genus: Chaetomorpha
- Scientific name: Chaetomorpha linum
- Common synonyms: Chaeto
Habitat
Chaetomorpha is a genus of filamentous green marine macroalgae (Cladophoraceae) of coastal waters worldwide; it grows as tangled, stiff, bright-green filaments resembling a ball of fishing line. In the Aquairi knowledge base, populations associated with this form are recorded from Cosmopolitan.
Growth requirements
- Lighting: high
- CO2: not required
- Temperature: 22-28 °C (72-82 °F)
- pH: 8-8.4
- GH: 8-12 °dGH
- Substrate: any
- Maximum height: 30 cm
- Growth rate: fast
- Recommended placement: floating
Placement
Kept loose in a refugium under strong light, where it tumbles in the flow; widely used for nutrient export of nitrate and phosphate from reef systems. In the Aquairi knowledge base this form is recommended for the floating layer under high light and without obligatory CO2 injection, using any substrate.
Propagation
Grows simply by elongation and fragmentation, so harvesting a portion of the ball both prunes it and removes captured nutrients. Documented propagation techniques for this entry include: stem cuttings.
Common issues
It can trap detritus and small livestock in its mass and may host pest organisms; periodic rinsing and harvest keep the colony clean and productive.
Propagating Chaetomorpha (Chaeto) Macroalgae
Overview
Chaetomorpha is a marine green macroalgae made up of macroscopic filaments that are one cell thick and unbranched; this lack of branching distinguishes it from related algae. It is popular with aquarium hobbyists, kept in saltwater refugiums where it exports organic nutrients and offers a refuge for beneficial microfauna like copepods.
It is not a substrate stem plant but a free-floating tangle that grows as a loose ball or mat. It is considered the easiest macroalgae to grow and harvest in a refugium, growing fast and rarely crashing.
Propagation Method
Propagation could not be simpler: the alga reproduces by filament fragmentation, so you just pull off or divide a portion of an established clump and let both halves continue tumbling and growing under light and flow.
Step-by-Step
- Lift a handful from an established, healthy clump in the refugium or sump.
- Pull it apart or divide it into the portions you need — no cutting tools or attachment are required.
- Place each portion back into the refugium under the light, leaving room to tumble.
- Harvest excess regularly to keep active growth, since growing algae is what drives nutrient export.
- Use harvested portions to seed another refugium or share with other reefers.
Conditions for Healthy Growth
Light the refugium well, around 6700K; some aquarists run the light 24/7 so the macroalgae outcompetes nuisance algae in the display. Keep flow low so detritus settles, while ample nutrients (nitrate and phosphate) from the system feed fast growth. For real nutrient reduction, run a large amount — far more than you might expect.
Maintenance
The core maintenance is regular harvesting: removing a portion every couple of weeks keeps the colony in active growth, and each harvest is itself a propagation event that physically exports the nutrients locked in the tissue.
Common Challenges
Too little light or flow leaves the inner mat shaded and clogged with detritus; too small a clump exports little. Never dump specimens into waterways — improper disposal has established invasive non-native populations, so boil, freeze or dry surplus before discarding.