Aplysina archeri (also known as stove-pipe sponge because of its shape) is a species of tube sponge that has long tube-like structures of cylindrical shape. Many tubes are attached to one particular part of the organism. A single tube can grow up to 5 feet (1.5 m) high and 3 inches (7.6 cm) thick. These sponges mostly live in the Atlantic Ocean: the Caribbean, Bahamas, Florida, and Bonaire. They are filter feeders; they eat food such as plankton or suspended detritus as it passes them. Very little is known about their behavioral patterns except for their feeding ecology and reproductive biology. Tubes occur in varying colors including lavender, gray and brown. They reproduce both by asexual and sexual reproduction. When they release their sperms, the sperms float in water and eventually land somewhere where they begin to reproduce cells and grow. These sponges take hundreds of years to grow and never stop growing until they die. Snails are among their natural predators. The dense population of these sponges is going down because of toxic dumps and oil spills.
(From Wikipedia, February 2015)