Caulerpa lentillifera Care Guide
Caulerpa lentillifera, the edible 'sea grapes' macroalga, is a fast-growing siphonous green seaweed widely used for nutrient export in marine refugiums.
Compiled by Aquairi from published sources · Published · Updated
Overview
Caulerpa lentillifera J.Agardh, 1837 is a green macroalga of the family Caulerpaceae, commonly called sea grapes. Like other Caulerpa, it is a siphonous alga: the whole thallus is effectively a single giant cell with many nuclei. Creeping stolons bear upright shoots covered in cluster-like green beads, and the alga is widely cultivated as food across the Asia-Pacific.
Taxonomy
- Family: Caulerpaceae
- Genus: Caulerpa
- Scientific name: Caulerpa lentillifera J.Agardh, 1837
- Class: Ulvophyceae; Order: Bryopsidales
- WoRMS AphiaID: 211475 (accepted)
Habitat
The species occurs in coastal regions of the Indo-Pacific. It was first cultivated commercially in the 1950s in Cebu, the Philippines, after an accidental introduction to fish ponds, and is grown in Okinawa, Japan, and elsewhere. In cultivation it is harvested after about two months and then on a recurring schedule as it regrows.
Aquarium use
In reef systems Caulerpa lentillifera is kept mainly in refugiums for nutrient export, where its fast growth removes nitrate and phosphate from the water. The beads and stolons also provide grazing surface and habitat for small invertebrates such as copepods.
Tank requirements
- Water type: saltwater (marine)
- Temperature: 22-28 °C (72-82 °F)
- pH: 8.0-8.4
- Carbonate hardness / GH reference: 8-12 °dGH
- Lighting: medium
- CO2 injection: not required
- Growth rate: fast; maximum height ~10 cm
Care and propagation
Caulerpa spreads by stolon division, so regular trimming keeps the patch healthy and sustains nutrient uptake. As with all Caulerpa species, leave enough biomass to continue export when harvesting. Trimming roughly every two weeks helps prevent the build-up of old tissue.
Propagating Caulerpa lentillifera (Sea Grapes)
Overview
Caulerpa lentillifera, sea grapes or green caviar, is an edible marine green macroalga that can grow to about 30 cm. Instead of leaves it carries rounded bead-like ramuli on creeping stolons; the beads burst in the mouth with a fresh umami, ocean-like taste, and it is eaten raw in salads.
Like all Caulerpa it is a siphonous alga — a giant single cell with many nuclei. It has been commercially cultivated since the 1950s in Cebu, the Philippines, and is widely grown in refugiums for nutrient export.
Propagation Method
Sea grapes are propagated vegetatively by fragmentation and division of the stolon. Each piece of creeping runner bearing healthy beads and rhizoids will re-anchor and grow into a new clump — this runner division, not substrate cuttings, is how both refugiums and aquaculture farms multiply it.
Step-by-Step
- Select a vigorous length of stolon carrying plump green beads.
- Separate it from the parent by pinching or cutting the runner.
- Place the fragment on rubble or mesh in the refugium or culture tank so rhizoids re-attach.
- After about two months for a fresh start, then every couple of weeks, harvest the new growth.
Conditions for Healthy Growth
As a tropical marine species it needs stable marine conditions: full salinity, alkaline pH near 8.0–8.4 and warm water. In aquaculture it is grown in shallow ponds and tanks; in the reef tank a lit refugium serves the same role.
- Full-strength salinity and alkaline marine pH.
- Medium lighting on a steady photoperiod.
- Dissolved nitrate and phosphate to fuel its fast, nutrient-exporting growth.
Maintenance
Harvest on a regular cycle — farms crop it roughly every two weeks once established. Frequent harvesting keeps it actively growing, maximises nutrient export and is the best safeguard against it going sexual.
Common Challenges
The going-sexual crash is the main risk in a closed system. As with the whole genus, never release Caulerpa into the wild, since several Caulerpa species are notoriously invasive escapees from the aquarium trade.