Acropora samoensis

Acropora samoensis is a digitate to corymbose Acropora in the humilis group, built from thick, sturdy branches rather than delicate ones. Its robust form makes it one of the more substantial-looking small-polyp stony corals. In aquaculture it appears in green-yellow, purple, and blue, with colour usually strongest on the upper surfaces and branch tips.

Care

An advanced species for a mature, stable SPS system. Alkalinity stability comes first — avoid swings, test routinely, and correct slowly — with calcium and magnesium kept consistent in balance. Its thick branches demand high, strong random flow to keep polyps extended and prevent detritus settling between branches; never aim a constant jet at the colony, as even robust Acropora will lose tissue on the blasted side. Light is high, with PAR 250–400 as the working range, acclimated gradually. Health is shown by a firmly encrusting base, thick unbroken tissue, and regular polyp extension.

Placement and growth

Place it at the top of the rockwork in the brightest, most turbulent zone you have. Allow at least 2 in of minimum clearance around it so its thick branches are not shaded and flow is not blocked as the colony broadens. Growth is moderate and solid rather than fast; a colony that bases down well will thicken and extend digitate branches steadily over time.