Livestock | Marine | Marine Inverts and Snails | Scallops and Clams

Keeping Clams and Scallops in Marine Aquariums

Clams and scallops are some of the most captivating bivalves found in marine aquariums. Known for their iridescent colors and filter-feeding capabilities, these invertebrates can serve both aesthetic and functional roles in reef systems. While clams, especially Tridacna species, are popular for their vivid mantles and photosynthetic nature, scallops are dynamic and fascinating filter feeders.

General Care Tips:
Clams and scallops thrive in stable, mature reef tanks with excellent water quality, strong lighting, and adequate flow. Ideal water parameters include a temperature range of 72–81°F and a pH of 8.1–8.4. Calcium, alkalinity, and magnesium levels should be maintained consistently to support healthy shell growth—especially important for clams.

Feeding:

• Clams (Tridacna spp.): Most are photosynthetic, thanks to symbiotic zooxanthellae in their mantles. They require strong lighting (LED, T5, or halide) and can benefit from supplemental feedings of phytoplankton, especially when young or newly introduced.

• Scallops (e.g., Lima spp., Ctenoides spp.): Non-photosynthetic filter feeders that rely entirely on suspended planktonic food. Regular feedings with phytoplankton, marine snow, or liquid invertebrate food are essential for their survival.

Compatibility and Behavior:
Clams and scallops are peaceful and reef safe but require proper placement to avoid damage. Clams typically prefer stable, flat rock surfaces or sandy substrate, while scallops prefer lower light areas with moderate flow to stay suspended or nestled among rocks. Avoid placement near aggressive corals or anemones. Fish like puffers or certain wrasses may nip at clam mantles, so choose tankmates wisely.

Popular Clam Species:

• Tridacna crocea: Compact and vibrant, ideal for mounting in rockwork; photosynthetic.

• Tridacna maxima: Popular for intense coloration; prefers strong lighting and moderate flow.

• Tridacna derasa: Easier to keep and faster growing, good for sandy areas in larger tanks.

• Tridacna squamosa: Distinctive fluted shell; grows large and needs space.

• Hippopus hippopus: Hardy and unusual, with a wider shell shape—ideal for sand beds.

Popular Scallop Species:

• Lima scabra (Flame Scallop): Bright red with waving tentacles; filter feeder, not photosynthetic.

• Lima orientalis: Similar to flame scallops but typically orange or yellow; needs regular feeding.

• Ctenoides ales (Electric Flame Scallop): Known for its bioluminescent-like flickering; requires expert care.

• Limaria fragilis: Small, delicate, and good for nano setups with proper feeding.

Special Considerations:
Clams require strong lighting and stable calcium and alkalinity for shell development, while scallops need frequent target feeding to avoid starvation. Both are sensitive to poor water quality, especially high nitrates or copper. Avoid handling bivalves directly or exposing them to air unnecessarily, as it can stress or injure them.

Summary:
Clams and scallops are beautiful, fascinating additions to marine aquariums that reward proper care with striking color and unique behavior. Clams are more beginner-friendly with strong lighting and stable parameters, while scallops require dedicated feeding and are better suited to experienced aquarists. Both bring elegance and natural filtration to well-maintained reef tanks.