Characters: Colonies are submassive, columnar or encrusting and commonly exceed 2 metres across in turbid water. Corallites sometimes vary greatly in size depending on where they occur on the colony; they are usually 3-4.5 millimetres diameter. Usually eight to twelve septa reach the corallite centre. Tentacles are seldom fully extended during the day. Colour: Usually grey, also pink, green or brown. Similar species: Galaxea paucisepta, which has smaller corallites. See also G. cryptoramosa. Habitat: Reef environments protected from strong wave action. Abundance: Common