Maxima Ultra Clam

Maxima Ultra Clam: The Giant of the Small Giants

The Maxima Ultra Clam (Tridacna maxima) is a highly desirable, large specimen of the Maxima species, typically referring to those available for sale in the 5 to 6-inch range and exhibiting the most intense, vibrant coloration and mantle patterns (often branded as 'Ultra,' 'Electric,' or 'Gold' grade). While T.maxima is often called the "Small Giant Clam," these larger specimens are a substantial addition to any mature reef system.

Native to the shallow, clear waters of the Indo-Pacific, the Maxima Ultra Clam relies heavily on the symbiotic zooxanthellae algae in its mantle for survival, meaning intense, high-quality reef lighting is its most crucial requirement. Its deeply fluted shell and spectacular, intricate patterns of electric blues, greens, golds, and purples make it a top-tier showpiece.

Due to its high demand for light, pristine water quality, and the stability required to grow a clam to this large size, the Maxima Ultra Clam should only be attempted by Intermediate to Advanced hobbyists with a well-established reef tank.

Diet & Compatibility:

• Diet: The Maxima Ultra Clam is primarily a Photosynthetic Filter Feeder. It receives the vast majority of its energy from the sun via its symbiotic algae (zooxanthellae). As a large adult, it is mostly self-sufficient but will still filter feed on phytoplankton, bacteria, and particulate organic matter from the water column.
• Feeding in Captivity: Clams of this size (5−6 inches) typically do not require dedicated supplemental feeding if housed in a well-stocked, nutrient-rich reef tank, though occasional phytoplankton dosing can be beneficial. Pristine water quality and intense light are far more critical than target feeding.
• Lighting: Extremely High Intensity is non-negotiable. Place the clam high on the rockwork where it receives PAR levels comparable to high-light SPS corals. Insufficient light will lead to starvation and bleaching.
• Placement & Attachment: It prefers a solid, hard substrate like live rock or a clam stand/tile and must be placed where its entire mantle receives direct light. It attaches with byssal threads and should never be forcibly removed once attached, as this can be fatal. Ensure the clam has plenty of room to grow and open fully.
• Water Flow: Requires moderate, turbulent, and indirect water flow to bring nutrients and oxygen. Strong, direct currents that cause the mantle to flap are stressful and should be avoided.
• Reef Compatibility: It is Reef Safe and peaceful. It is vital to monitor for predators, most notably tiny, parasitic Pyramid Snails which attach to the clam's shell. Aggressive fish like certain puffers, angelfish, or butterflyfish may nip the mantle and should be avoided.
• Water Quality: Requires immaculate and highly stable parameters to build its shell:
  • Calcium: 400−450 ppm
  • Alkalinity: 8−12 dKH
  • Magnesium: 1280−1350 ppm

Quick Facts

• Scientific Name: Tridacnamaxima (Ultra Grade)
• Primary Common Name: Maxima Ultra Clam
• Other Common Names: Small Giant Clam, Electric Maxima
• Origin: Indo-Pacific (Aquacultured or Maricultured)
• Max Size: 6−12 inches (15−30 cm)
• Temperament: Peaceful
• Diet: Photosynthetic Filter Feeder (Relies on light and zooxanthellae)
• Minimum Tank Size: 75−100+ Gallons (For stability and light penetration)
• Reef Compatibility: Yes
• Lighting Requirement: Very High (SPS/Acropora Level)
• Care Level: Intermediate to Advanced