Description
Rock Flower Anemone (Phymanthus crucifer)
The Rock Flower Anemone is a colourful marine anemone popular in reef aquariums for its vibrant patterns, distinctive flower-like appearance and relatively manageable care requirements. It is commonly found attached to rocky or sandy substrates in the Caribbean and western Atlantic. Unlike many other anemones, it generally stays in one location once settled and is not known for frequently wandering around the aquarium. It can capture small fish and invertebrates, so careful placement is important.
Lighting
Moderate to High: Can adapt to a range of lighting conditions.
Generally does well under moderate reef lighting, with gradual acclimation to stronger light.
Does not require extremely intense lighting.
Placement (Aquarium Zone)
Bottom to Lower Rockwork: Often settles on or between rocks, sometimes partially buried in sand.
Provide a stable surface where its pedal disc can attach securely.
Leave adequate space around it to prevent contact with neighbouring corals.
Temperature
• 24–27°C (75–81°F)
Salinity
• 1.023–1.026 specific gravity
pH
• 8.1–8.4
Alkalinity
• 7–11 dKH
Calcium
• 380–450 ppm
Magnesium
• 1,250–1,400 ppm
Low to Moderate: Prefers gentle, indirect water movement.
Avoid strong, direct flow that causes the oral disc or tentacles to remain compressed.
Maintain enough circulation to prevent debris from collecting around its base.
Diet
Carnivore: Captures small meaty foods using its tentacles.
Can be fed small portions of mysis shrimp, finely chopped shrimp, and other suitable marine foods.
Feed sparingly, around once or twice a week, adjusting to the animal's size and condition.
Avoid large food portions that may remain uneaten and pollute the water.
Adult Size (up to)
• Approximately 10–15 cm (4–6 inches) across, although some specimens may grow larger.
Growth Rate
Slow to Moderate: Grows gradually under stable aquarium conditions.
Can reproduce sexually and, less commonly, through asexual reproduction.
Care Level
• Moderate: Generally more manageable than many host anemones, but still requires stable water quality, suitable lighting and careful placement.
Reef Compatibility
Generally Reef Compatible with Caution: Usually does not actively seek out and sting neighbouring corals, but its tentacles can sting nearby animals.
May capture small fish, shrimp or other small invertebrates.
Keep sufficient space between the anemone and corals.
Temperament
Generally Stationary: Usually remains attached once established.
Can sting animals that come into contact with its tentacles.
