Derasa Clam

The Derasa Clam (Tridacna derasa) is a peaceful species that is reef-safe, admired for its striking mantle coloration, intricate patterns, impressive size, and unique ability to filter water. Unlike fish, clams are not sexually dimorphic in appearance—juveniles are typically smaller with developing mantle coloration, while adults exhibit brighter, more vivid patterns and larger, thicker shells.

They can reach about 20 inches in adulthood and should be housed in aquariums of at least 100 gallons. Provide a stable sandbed or flat rock base for secure attachment, strong lighting for photosynthesis, and stable water parameters (salinity ~1.020–1.025, temp ~72–79°F, pH ~8.1–8.4).

Though primarily photosynthetic due to their symbiotic zooxanthellae, Derasa clams also benefit from supplemental feeding when young. Diet should consist of phytoplankton, marine snow, and dissolved nutrients in the water column. With proper care, this clam makes a standout addition to reef aquariums, offering both beauty and natural filtration.

International Aquatics Quarantine & Guarantee: All fish are checked by marine vets, given a formalin bath, and held for 14 days in copper-treated systems. We feed Selcon-soaked food with Kanaplex and Metroplex during quarantine. Unless marked, all livestock comes with our 15-Day Guarantee. You will receive a video of your fish eating before shipment. On request, we also send photos/videos after arrival at IA. Some species are import-to-order (3-10 business days). Many common species are already cleared or near the end of QT.

Several species will be import-to-order and may take anywhere from 3-10 business days to secure. Once your fish is secured, you will be notified, and the quarantine process will then begin.