Marine & AlgaeAdvanced🌤️ Bright indirect

Jointed tuft algae

Cymopolia barbata · also called Jointed tuft, Tufted joint algae, Beaded algae, Cymopolia

🐾 Pet-safe

Generally non-toxic to cats and dogs.

Cymopolia is a heavily calcified green macroalgae that grows as segmented, bead-like jointed stems, each cylinder topped with a small fuzzy green tuft of filaments — like a string of calcified beads with green pom-poms. It is a distinctive sculptural display macro, but like other calcified macros it demands stable calcium/alkalinity and a mature system.

Educational only. KinStation content is reviewed by licensed veterinarians but cannot replace an in-person exam. Always consult a licensed veterinarian or board-certified specialist for diagnosis, treatment, or any decision affecting your pet's health.

Quick facts

Category	Marine & Algae
Family	Dasycladaceae
Native origin	Tropical western Atlantic and Caribbean reef and lagoon habitats
Care difficulty	Advanced
Light	Bright indirect
Pet toxicity	Pet-safe

Light

Wants moderate-to-strong reef lighting (medium-high aquarium light / good PAR) to support its heavy calcification, similar to Halimeda. Display reef or strong refugium LEDs both work; poor light leads to decline. Mapped here to bright lighting needs.

Water

Standard reef parameters: temperature 23-27 C (74-80 F), salinity ~1.025 SG, pH 8.1-8.4. Because it is heavily calcified it needs well-maintained calcium (~400-450 ppm), alkalinity (8-11 dKH), and magnesium (~1300 ppm), and it competes with corals for these. Uses some nitrate/phosphate but is not a strong exporter. No CO2 (marine).

Soil & potting

Attaches with a holdfast and is often associated with rubble/rock; in the aquarium it is wedged into or attached to rockwork. The calcified jointed stems grow upward from the base. Not planted in nutrient substrate; no aquasoil or root tabs — it feeds from the water column and calcifies from dissolved minerals.

Environment — humidity, temperature, placement

Submersed only. No CO2 (marine). Moderate flow keeps detritus off the beaded segments. A display macro for the midground/foreground of a mature reef or macro tank. Its gritty, calcified texture resists grazing, so it survives in herbivore tanks. Reef-safe.

Propagation

Grows by adding new calcified segments and branching, and can send up new stems from the base. Like other heavily calcified macros it is not easily fragmented by cutting; it is generally left to grow and multiply on its own. Remove bleached/dying segments to avoid nutrient release.

Toxicity detail

Reef-safe and non-toxic to fish, corals, and shrimp; its calcified tissue deters most grazers. Not invasive or regulated in the aquarium hobby. As with all macros, never release into the wild.

Growth stages

How this plant changes through its life — each stage often has its own care, diet and space needs.

Photo coming soon

Spore / recruit

Aquatic plants and macroalgae establish from spores, seeds, or drifting fragments that settle and attach to substrate or rock. Many freshwater aquarium plants and marine macroalgae also spread readily from a detached piece that takes root or holdfast.

Photo coming soon

Young growth

Young growth puts out its first blades, fronds, or leaves and anchors with roots or a holdfast. Submersed plants may look different from their emersed form, and growth speeds up as the plant adapts to the water's light and nutrients.

Photo coming soon

Mature

A mature aquatic plant or macroalga reaches its full size and characteristic shape, forming the dense growth, runners, or fronds typical of the species. Established plants spread to fill space and can be divided or trimmed to propagate.

Reviewed and signed off by: KinStation Editorial — pre-launch draft (pending horticulture review) on 2026-06-10

Sources

Cymopolia barbata - Encyclopedia of Life (EOL) (encyclopedia)
Jointed Tuft (Cymopolia barbata) macroalgae - MosaicMacros (care guide)