China Clam

Hippopus porcellanus

Also known as Porcelain Clam, Smooth Horseshoe Clam, China Giant Clam

SaltwaterClam

Care at a glance

Temperature: 75–81°F (24–27°C)
pH: 8.1–8.4
Adult size: 15.7 in (40 cm)
Minimum tank: 106 gal (400 L)
Temperament: Peaceful
Social behavior: Solitary
Swim level: Bottom
Difficulty: Difficult
Breeding: Hard
Rarity: Very rare
Reef safe: Reef safe
Origin: Coral Triangle around the Philippines, on shallow reef flats and sandy lagoons.
Family: Cardiidae

Overview

This is a big clam that needs a large, mature reef of 400 litres or more at 24 to 27 C and pH 8.1 to 8.4 with intense light and rock solid calcium and alkalinity. Small ones benefit from phytoplankton feeding, while large ones live mainly off light. It is peaceful and reef safe but demands stable water and a lot of room, and it shows up in the trade only occasionally.

In the wild

The china clam is a large giant clam with a smooth, pale shell that has a porcelain-like finish and a mantle usually in muted browns and golds with fine patterning. The shell edges meet more evenly than the toothy gape of its cousin the horse hoof clam. Big ones can pass 40 cm.

Good to know

Hippopus porcellanus has one of the smallest natural ranges of any giant clam, centered on the Sulu Sea and Palawan region of the Philippines. Like other giant clams it lives off light, hosting zooxanthellae algae in its mantle, and it is rare enough to be a conservation concern.