Favia

An encrusting brain coral with rounded corallites packed across a dome, each corallite keeping its own separate wall so a visible groove runs between neighbors. Sweeper tentacles come out at night and burn anything within a few inches. PAR 75–150, moderate flow.
Favia, Favites, Dipsastrea — what the names mean. Most of what the hobby calls favia has been reclassified into Dipsastrea, and the old split from Favites came down to the walls between corallites: favia has separate walls for each polyp, favites shares them, which is why favites is sometimes called the honeycomb or maze coral. For your tank the distinction changes nothing. They want identical care.
These are the workhorses of a mixed reef. Moderate light, moderate flow, low to middle placement, and a tolerance for parameter drift that few other LPS match. If you have killed acans by getting the light wrong, a favia is where to rebuild your confidence.
They sting harder than they look. Sweeper tentacles come out at night and can reach several inches beyond the visible edge of the colony. The classic mistake is placing a favia next to a prized acan or chalice and finding a dead patch two weeks later. Give it clear space and check what is downstream of it.
Feeding is optional but visible: a favia fed weekly with the flow off will thicken its tissue and deepen color, especially the reds and greens people buy them for.
How to identify it in the Coral Field GuideWhat UPS Next Day Air for a live animal actually costsUPS Next Day Air for a livestock box costs us about $30 inside Florida and between $45 and $75 everywhere else in the lower 48. We charge $30 in Florida and $50 elsewhere, which means on most out-of-state orders we are already absorbing part of it, and above a $349 livestock subtotal we cover the whole thing. We would rather tell you that than pretend shipping a living animal overnight is cheap. Orders leave Key West Tuesdays and Wednesdays so nothing sits in a truck over a weekend.