Clams and Bivalves

Tridacna maxima is a popular, highly sought-after, and challenging (intermediate-level) reef aquarium clam known for its intense, varied mantle colors (blue, green, gold, purple) and intricate patterns. They require high-intensity lighting, stable water parameters (calcium 400-440 ppm), and a rocky substrate for attachment. Maximas are smaller, growing up to 12-16 inches, and prefer to be placed high in the tank with moderate to high water flow.  Key Characteristics & Requirements:  Appearance: Features highly variable, vibrant mantles with spots, stripes, or mottled patterns. Their shells are less symmetrical than other clams, with small scutes. Size: Generally grows to around 12 inches (30 cm) in aquariums, though some may grow slightly larger. Lighting: Requires intense lighting (Metal Halide or high-output LED). Placement: Must be placed on a hard, rocky surface where they will attach using byssal threads. Flow: Prefers moderate to high, chaotic water movement rather than simple, laminar flow. Diet: Primarily photosynthetic (symbiotic algae), but smaller specimens (inches) benefit from frequent phytoplankton feedings. Placement Strategy: Ideal for placing in rocky, high-light areas of the reef scape.  Aquarium Compatibility & Care:  Difficulty: Intermediate. Temperament: Peaceful. Reef Safe: Yes. Tank Size: 75-100+ gallons. Acclimation: Requires slow acclimation to lighting to avoid bleaching. Potential Hazards: Beware of parasites like pyramidellid snails and fish that may pick at the mantle (e.g., angelfish, wrasses). 

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