All bryozoans are colonial and most are marine.
Bryozoans are most abundant in temperate-tropical waters that are not too turbid. They require a hard or firm substrate on to which the attach to or encrust, and clear agitated water from which they obtain their suspended food. Enclosed within a skeleton of calcite, bryozoans have a sac-like coelomate body with a well defined mouth, anus, and other specialized organs. The classification follows your text in treating the Bryozoa and Brachiopoda as separate phyla. The colony of bryozoan animals.