A wooden fish sometimes known as a Chinese block, is a wooden percussion instrument similar to the Western wood block. The wooden fish is used by monks and laity in the Mahayana Buddhist tradition. It is often used during rituals usually involving the recitation of sutras, mantras, or other Buddhist texts. The wooden fish is mainly used by Buddhist disciples in China, Japan, Korea, and other East Asian countries where the practice of Mahayana, such as the ceremonious reciting of sutras, is prevalent. In most Zen/Ch'an Buddhist traditions, the wooden fish serves to keep the rhythm during sutra chanting. In Pure Land Buddhism, it is used when chanting the name of Amitabha.
The Taoist clergy has also adapted the wooden fish into their rituals.
There are two kinds of wooden fish.
Most commonly today, it is the traditional instrument that is round in shape and often made out of wood (often made out of lumber); this form is actually a later development from the original. The fish is hollow with a ridge outside of the wooden fish to help provide the genuine hollow sound when striking the fish (the instrument is similarly shaped like a jingle bell). The sound can differ amongst wooden fish depending on the size, type of wood used, and how hollow the wooden fish is. The instrument is carved with fish scales on its top, and a carving of two fish heads embracing a pearl on the handle (to symbolize unity), hence the instrument is called a wooden fish for that reason. In Buddhism the fish, which never sleeps, symbolizes wakefulness. Therefore, it is to remind the chanting monks to concentrate on their sutra. Often the mallet used to strike the fish has a rubber coated tip to provide a muffled, but clear sound when struck. A simplified form is given in the temple block.
Wooden fish come in many sizes and shapes, ranging from 150 millimetres (5.9 in), for laity use or sole daily practice, or to 1.2 metres (3.9 ft) for usage in temples. Wooden fish are often (in Chinese temples) placed on the left of the altar, alongside a bell bowl, its metal percussion counterpart. Wooden fish often rest on a small embroidered cushion to prevent damage and unpleasant knocking sounds caused from the fish lying on the surface of a hard table or ground, as well as to avoid damage to the instrument.