Staghorn Coral

About

Found across upper reef slopes and lagoons throughout the Indo-Pacific, Acropora aculeus is a corymbose (table-like) coral with a distinctly fine and airy architecture. Its horizontal branches spread outward while slender upward-projecting branchlets give the colony a almost feathery appearance up close. One of the more subtle structural details is that the axial and radial corallites at the branchlet tips aren't sharply differentiated from one another, giving the tips a tapered, uniform look. The radial corallites along the branch sides are nariform, nostril-shaped, with slightly flared lips, a useful identification feature when you're trying to sort one Acropora from another. Coloration can be genuinely variable: base colonies are often grey, but bright blue-green and yellow morphs exist, and branch tips frequently show contrasting yellow, lime green, pale blue, or brownish tones. In the wild this species ranges from shallow depths of around 3 meters down to about 35 meters, giving it some flexibility in light exposure. In the aquarium it is firmly in the advanced category. Like most small-polyp stony corals it demands consistently high water quality, intense lighting, and strong, well-distributed flow. Not a coral for a system that's still finding its stability.