Briareum violaceum: living card for green star polyps

Briareum violaceum (green star polyps) brings motion and hardiness to a reef, then punishes poor placement. Once it reaches the main rockwork, the problem is controlling a successful colony.

Quick read

• Type: encrusting octocoral with extended polyps.
• Aquarium: stable reef with isolated rock or controlled wall.
• Light: medium.
• Flow: moderate, enough to wave the polyps.
• Indicative temperature: 24-26 C.
• Salinity: 1.024-1.026 SG.
• Alkalinity: 8-10 dKH.
• Calcium: 400-450 mg/L.
• Difficulty: low; invasive if neglected.

What to check before placing it

Look for a firm mat with no black zones or embedded algae. Polyps may close during transport, but the base tissue should look healthy.

Before gluing a colony, think about its future size, the direction of flow, and whether you could remove it without dismantling half the rockwork if something goes wrong.

Placement and coral reading

Think like a gardener: a separate island gives motion and removable excess. On main rockwork, plan a physical boundary.

Read the first week outside the blue-light photo. Watch extension, tissue, response to flow, and irritation signs when the aquarium is in its normal rhythm.

Working parameters

It tolerates moderate nutrients and suffers more from swings than imperfect numbers. Avoid total shade and constant sediment.

In a reef, stability means repetition: salinity, alkalinity, temperature, and nutrients inside a window the aquarium can sustain, not perfect numbers from one test.

Compatibility and warning

Do not place it beside corals it must not invade. Its aggression is spatial: it covers, shades, and wins by persistence.

If it stops opening, check bacterial film, sediment, salinity, and algae smothering the mat.

Reference sources

WoRMS for taxonomic reference; LiveAquaria, Tidal Gardens, and specialist reef guides for practical light, flow, and stability ranges. Values are indicative and must be adapted to the real history of the system.