Description
RF Crocea Clam (Tridacna crocea)
The Crocea Clam, also known as the Boring Giant Clam, is a beautiful and highly sought-after giant clam known for its vibrant mantle colours, including blue, green, turquoise and gold patterns. It naturally lives embedded in hard coral rock, where it uses its strong foot to attach itself securely. It is photosynthetic and relies heavily on intense lighting, making it best suited to mature, stable reef aquariums. It can also filter microscopic food particles from the water.
Lighting
High to Very High: Requires strong lighting to support its symbiotic zooxanthellae.
Best kept under high-output LED or T5 reef lighting.
Acclimate gradually to intense lighting to prevent bleaching or stress.
Insufficient lighting can cause gradual decline.
Placement (Aquarium Zone)
Lower to Middle Rockwork: Place on a stable rock surface where it can attach securely.
Often prefers to embed itself partially into suitable rockwork.
Avoid placing it directly on sand, where it may be unstable or vulnerable to predators.
Ensure it has enough room to expand its mantle fully.
Temperature
- 24–27°C (75–81°F)
Salinity
- 1.024–1.026 specific gravity
pH
- 8.1–8.4
Alkalinity
- 8–9 dKH
Calcium
- 400–450 ppm
Magnesium
-1,250–1,400 ppm
Flow
Moderate: Requires gentle to moderate, indirect water movement.
Avoid strong, direct flow that causes the mantle to retract or remain disturbed.
Good circulation helps deliver nutrients and remove waste.
Diet
Photosynthetic Filter Feeder: Obtains most of its energy from symbiotic zooxanthellae living within its mantle.
Also filters microscopic plankton and suspended organic particles from the water.
Smaller specimens may benefit from supplemental phytoplankton or suitable fine-sized filter-feeder foods.
Larger specimens generally depend more heavily on photosynthesis and do not require frequent direct feeding.
Adult Size (up to)
- Approximately 15–20 cm (6–8 inches) in aquariums, although larger specimens can occur in the wild.
Growth Rate
- Moderate: Growth depends on lighting, calcium availability, alkalinity, nutrition and overall water stability.
Care Level
- Advanced: Requires intense lighting, stable water chemistry and careful acclimation. Sensitive to sudden changes in water quality.
Reef Compatibility
Reef Safe: Generally compatible with corals and other reef inhabitants.
Its mantle can be irritated by neighbouring corals, aggressive fish or invertebrates.
Certain fish, pyramidellid snails and other predators may attack the clam.
Temperament
Peaceful and Stationary: Attaches firmly to rockwork and generally remains in one location.
Can retract its mantle and close its shell rapidly when disturbed.
Special Requirements
Provide strong, consistent lighting and stable calcium and alkalinity levels to support shell growth.
Inspect regularly for pyramidellid snails, especially around the shell edges and byssal opening.
Avoid placing it near aggressive corals or animals that may irritate its mantle.
Keep clam-eating fish and known predators away.
Avoid repeatedly moving it once its byssal threads have attached. Never pull it away from rockwork; cutting or tearing these threads can seriously injure the clam.
Maintain excellent water quality and avoid sudden fluctuations in salinity, temperature or alkalinity.
