Tridacna derasa

(Roding, 1798)

Derasa Clam, Smooth Clam

Range: Indo-West Pacific Ocean.

Size: 20 inches (50 cm)

Natural Environment: Inhabits outer coral reef platforms and mostly seen at depths between 10 - 85 feet (3 -25 m).

General Husbandry: Has a thick smooth shell and usually has a brown mantle with tan strips, with the mantle edged with fluorescent green.

They are also filter feeders and almost constantly filter the water for small particulates. Small specimens, < 2 - 3 inches can be fed a phytoplankton or greenwater supplement at least three times per week, which may encourage their growth. Larger specimens will do extremely well without any additional feedings.

So as not to repeat some of the Introduction to this section, review it for more information on their aquarium husbandry.

Taxonomy:

Kingdom: Animalia

Phylum: Mollusca

Class: Bivalvia

Subclass: Heterodonta

Order: Cardiida

Superfamily: Cardioidea

Family: Cardiidae

Subfamily: Tridacinae

Genus: Tridacna

FYI: Mariculture stock available.

Considered a food item throughout the Far East and Indo-Pacific region.

Does not burrow into the substrate.

The hardiest of all Tridacna clams.

Experience Level: Intermediate

Diet: Photosynthetic/Omnivore

Temperament: Peaceful

Aquarium Environment: Reef or fish-only aquarium

Coral Safe: Yes

Fish Safe: Yes

Invertebrate Safe: Yes

Acclimation Time: 30 minutes+

Aquarium Hardiness: Moderately hardy

Calcium (Ca): 380 - 430 mg/l

Alkalinity: 2.5 - 3.0 meq/l

Phosphate (PO4): <0.05 mg/l

Magnesium (Mg): approx. 1350 mg/l (relate to specific gravity)

Temperature Range: 72 - 83°F (22 - 28°C)

Minimum Tank Size: 50 gallons

Lighting: PAR 300 - 400

Water Movement: WM 2

Specific Gravity: 1.023 - 1.025

pH: 8.0 - 8.4

Iodine/Trace Elements Monitor/as necessary to maintain quality seawater.