SUMMERLAND KEY, Fla. — David Vaughan plunges his right arm down to his elbow into one of nine elevated tanks where thousands of tiny colonies of coral are growing at an astonishing rate in shaded seclusion next to the Mote Tropical Research Laboratory.

“Now this is the exciting part. You ready for this?” he asks, straining to be heard over the relentless hiss of filtered saltwater squirting from a maze of pipes and plastic tubing into the shallow fiberglass tank, the size of a dining-room table.

Dr. Vaughan, a marine biologist who is executive director of the laboratory, retrieves a flat rock from the bottom. A chocolate-brown colony of brain coral, nearly eight inches wide, has grown on the stony surface, its distinctive fleshy, serpentine folds nearly covering the rock.

A year ago the colony began as inch-and-a-half-wide coral fragments cut with a band saw from the same parent colony. As if doused with a growth elixir, these coral “seeds” began to grow 25 times as fast as they would in the wild.