Description

Caulerpa sertularioides (Green Feather / Fern-like Caulerpa)

AT A GLANCE

Quick facts: Care level: Easy · Lighting: Moderate · Flow: Low–Moderate · Feeding: Absorbs nutrients from water (no direct feeding required)

WHY SHOULD I BUY THIS ALGAE?

Caulerpa sertularioides is a graceful, feathery green macroalgae that adds texture, movement, and vibrant color to marine aquariums. Its delicate, fern-like fronds make it visually striking in refugiums and display tanks while functioning as a natural nutrient exporter, absorbing nitrates and phosphates. This algae is also a safe and nutritious grazing substrate for herbivorous fish such as tangs, blennies, and rabbitfish, and provides shelter for copepods and other beneficial microfauna.

CARE LEVEL

Easy
Perfect for both beginner and experienced reef aquarists with stable water conditions.

WATER REQUIREMENTS & GENERAL CARE

Temperature: 22–28 °C
Salinity: 1.023–1.026 (32–35 ppt)
pH: 7.8–8.4
Nitrates (NO₃): 2–20 ppm
Phosphates (PO₄): 0.02–0.1 ppm

Stable water parameters with moderate nutrients support healthy growth and deep green coloration.

LIGHTING

Moderate
Photoperiod: 12–16 hours/day

Thrives under standard reef lighting. Moderate intensity encourages full, upright growth without bleaching.

PLACEMENT

Refugium, Sump, or Display Tank
Can be loosely planted in sand, rubble, or left free-floating

Ensure fronds are free to sway with water flow to prevent accumulation of detritus and encourage healthy growth.

FLOW

Low–Moderate

Gentle circulation keeps fronds moving, removes trapped detritus, and promotes nutrient uptake.

FEEDING

Photosynthetic: No direct feeding required
Nutrient Requirements: Absorbs dissolved nitrates, phosphates, and trace elements from water

Prune regularly to prevent overcrowding and maintain nutrient export efficiency.

COMPATIBILITY & BEHAVIOR

Temperament: Passive
Safe with all reef fish and invertebrates
Consumed by herbivorous fish (tangs, rabbitfish, blennies)
Provides habitat for copepods, amphipods, and other small microfauna

ADDITIONAL INFORMATION

Family: Caulerpaceae
Origin: Tropical and subtropical Indo-Pacific regions
Natural Habitat: Shallow reef flats, seagrass beds, and lagoons with gentle water movement
Growth Form: Upright, fern-like fronds; fast-growing and spreading

WHY WE RECOMMEND THIS ALGAE

✔ Fast-growing and hardy nutrient exporter
✔ Elegant fern-like fronds add movement and texture to tanks
✔ Safe and edible for herbivorous fish
✔ Provides habitat for microfauna and supports a balanced ecosystem

DISCLAIMER