Star Polyp Coral
Star Polyps are very popular because not only is it fun to watch
their little polyps sway in the flow of water, but they are easy
to propagate and will spread quickly throughout your aquarium.
Corals are part of a biological group known as
Cnidaria. Most Cnidaria have a mouth, or mouths, that opens into
one big body cavity. Due to the lack of a true digestive system,
this cavity acts in its place and after the food is broken down
the nutrients are then sent through the rest of the body as food.
There is also no excretory system; therefore the waste is sent back
through the mouth or secreted into the surrounding water.
Tentacles of varying size will usually surround
the mouth of Cnidaria. Most Cnidaria have tentacles with stinging
cells that can shoot tiny poison darts into their prey or can even
be used as a defense mechanism. Some corals lack tentacles and instead
cover themselves with a thin layer of mucus and use that to collect
bacteria and plankton as food. Some corals even use both of these
methods. Cnidaria can either be an individual animal or members
of a complex colony. These "Colony Corals" share the food
and nutrients taken in by each individual.
Corals have tiny living organisms that actually
live in their tissue. These are called zooxanthellae and they are
the reason why such strong lighting is needed in the saltwater aquarium.
These algae-like creatures provide the coral with oxygen and other
nutrients that are produced during photosynthesis. During this process,
the zooxanthellae take up carbon dioxide and provide nutrients to
Corals can use two different types of defense
mechanisms. One of which is a sweeper tentacle wherein the coral
reaches its tentacles out to try to damage another coral with nematocysts.
The other is when the coral releases a minute amount of toxin into
the water to poison another coral within certain proximity. Most
"Hard Corals" should not be placed within reach of another
Size: 4-6 inches
Care Level: Easy
Diet: Medium Light, Medium-High Flow
Acclimation Time: 1+ hour