Acanthastrea echinata - Medium

Acanthastrea ("Acan" for short) is a popular genus of fast-growing large polyp stony corals known for their hardiness and wide variety of colors and color combinations. They are often intensely colored, with mixtures of blue, red, green, orange, purple, and more. The soft tissue tends to be heavy with mottled coloring or stripes. Australian colonies are especially prized for their color.

The most common Acans are A. echinata and A. lordhowensis. They are very similar in appearance although "Lordhowensis" (or "Acan Lord") tends to have more defined individual polyps and "Echinata" tends to be less defined and more visually similar to the Chalice Corals like Echinophyllia. A few other less common species - A. bowerbanki, A. hillae, A. maxima and A. rotundoflora - are also sometimes available and have similar slight differences in the definition and size of individual polyps and corallites.

All Acanthastrea relies heavily on photosynthesis for growth and should be placed towards the middle of the tank in moderate lighting. They will also readily accept meaty foods such as mysis shrimp, baby brine shrimp and other similar items. They feed mostly at night and should be target-fed when the feeding tentacles are extended from the center of each corallite. The more often the coral is fed, the faster it will grow and the less intense the lighting is, the more often the coral will need to be fed.

Acanthastrea is considered a moderately aggressive coral and should not be placed close to other similar corals. They may extend sweeper tentacles to sting nearby colonies and may even extend their flesh over a close colony and digest it on contact. Echinata is considered the most aggressive of the Acans.

Acans are some of the most popular corals to propagate by home aquarists. They can be cut apart using a dremel or other sharp blade between individual polyps. Since Lordhowensis and Echinata have the most defined polyps, they are usually the easiest to be successfully fragged, particularly by novice "fraggers".