Green Bulb Anemone: The Clownfish Host

The Green Bulb Anemone (Entacmaea quadricolor), more commonly known as the Bubble Tip Anemone (BTA), is one of the most popular and hardy species of sea anemone available to marine aquarists. Its appeal lies in its vibrant coloration (green in this morph) and its unique, bulbous-tipped tentacles.

Native to the Indo-Pacific, including the Red Sea and the Great Barrier Reef, this anemone is a host species for a variety of Clownfish (Amphiprion spp.), including the popular Ocellaris and Percula Clownfish. The symbiotic relationship is a mesmerizing centerpiece in the home aquarium.

The Green Bulb Anemone is an impressive invertebrate, reaching a diameter of up to 12 inches (30 cm) or more in the wild, though it often remains more compact in captivity. It is a mobile creature and requires a well-established, stable aquarium of at least 30 gallons (75 gallons for larger or multiple specimens).

Diet & Compatibility:

• Diet: The BTA is a Carnivore and is primarily photosynthetic, deriving most of its energy from the symbiotic zooxanthellae algae in its tissues. However, it requires supplemental spot-feeding of meaty foods 1–3 times per week.
• Feeding: Feed small pieces of frozen, thawed, vitamin-enriched foods such as mysis shrimp, chopped fish, krill, or marine shrimp, placed directly onto its tentacles or oral disc. The anemone's bubbles may elongate if it is not receiving enough light or food.
• Reef Compatibility: Reef Safe With Caution. Anemones are aggressive toward corals and other anemones due to their potent stinging cells (nematocysts). The BTA will move freely around the rockwork until it finds an area with optimal light and flow, stinging and potentially killing any coral or clam in its path. Powerhead and overflow guards are essential.
• Temperament: Semi-Aggressive / Hostile to Corals. It is peaceful toward its symbiotic clownfish hosts but will sting other invertebrates and fish that trespass on its territory. It should be kept singly or with other Entacmaea quadricolor specimens, provided there is enough space.
• Environment: Requires a mature tank (6+ months established) with stable parameters. It needs Moderate to High lighting (LEDs, T5s, or Metal Halide) and Moderate, indirect water flow. It will attach its foot securely to a crevice in the rockwork.

Quick Facts

• Scientific Name: Entacmaea quadricolor
• Primary Common Name: Green Bulb Anemone
• Other Common Names: Bubble Tip Anemone (BTA), Four-Color Anemone, Rose Bubble Tip Anemone (Rose/Red Morph)
• Origin: Indo-Pacific (Widespread)
• Max Size: 12+ inches (30+ cm)
• Temperament: Semi-Aggressive (Hostile to Corals)
• Diet: Photosynthetic Carnivore (Requires meaty spot-feeding)
• Care Level: Moderate (Requires a very stable, mature tank)
• Minimum Tank Size: 30+ Gallons (75+ for large size/multiple splits)
• Reef Compatibility: With Caution (Will sting nearby corals/inverts)