Lesser Knob Coral

About

The lesser knob coral (Cyphastrea decadia) is an adaptable branching species with a growth habit that genuinely changes depending on where it settles. On firmer reef slopes, colonies tend to produce compact, tighter branches reminiscent of Acropora at a glance, thanks to the prominent axial corallites at each branch tip. Move to softer substrates like lagoon sand and rubble, and the same species opens up into looser, more sprawling colonies that are noticeably more fragile and need careful handling. Coloration runs toward the understated side, browns, greys, and creams are the norm, so this one wins no prizes for bold pigmentation, but it has a clean, textural quality that fits well in a mixed reef. In the wild it turns up across a broad range of reef settings, with lagoon environments being a particularly common home. The septa, typically numbering between ten and twelve, give the corallites a neat, orderly look up close. For aquarium keeping, Cyphastrea as a genus tends to be fairly tolerant, and this species is generally considered a reasonable choice for intermediate-level reef keepers who can provide steady moderate lighting and flow without overdoing either.