my profile  |  logon  |  help search  > Database salt water Vertebrates -- Select -- Angelfish Angelfish(Dwarf) Anthias Assessors Basslets Batfish Blennies Boxfish(Cowfish) Butterflies Butterfly(Banners) Cardinals Cat Fish Comets Damsels Damsels(Clowns) Dottybacks Dragonets Drumfish Eels Filefish Frogfish Goatfish Gobies Gobies(Darts) Grammas Groupers Hamlets Hawkfish Helmut Gurnards Hogfish Jacks Jawfish Lionfish Miscellaneous Moorish Idols Parrotfish Pipefish Porcupinefish Puffers Rabbitfish Rays Scorpionfish Sea Horses Sharks Snappers Soapfish Soldierfish Spine Cheeks Squirrelfish Surgeonfish(Tang) Sweetlips Tilefish Toadfish Triggerfish Wrasses Wrasses(ReefSafe) Invertebrates -- Select -- Anemones Cephalopods Clams Crabs Fan Worms Jellyfish Lobsters Scallops Sea Cucumbers Sea Slugs Sea Stars Sea Urchins Shrimp Snails Sponges Tunicates(Squirt) Corals -- Select -- Hard Corals (LPS) Hard Corals (SPS) Mushroom Corals Polyp Corals Sea Fans Soft Corals fresh water compatibility disease/health > Virtual Tanks > Resources > Articles > Reviews SALT WATER  - Coral Polyp Coral Green Star Polyp Clavulariidae Starburst Polyp Coral Clavulariidae Yellow Polyps Parazoanthidae Silver Branch Xenia Xeniidae Button Polyps Zoanthidae Submit A New Specimen additional commentary       Aggressive? If you only find this post inaccurate, please post one of your own to the contrary. However, if you find this post in violation of our Community Guidelines, so we can review it and help keep our community clean and friendly. Posted by Uzzbay on March 04 2007 post rating 100 (1 votes)      Well, obviously the coral is not going to move across the tank to attack something. However, corals are still living animals and they are territorial over the spot they are residing in. So, their acts of aggression are based upon the idea of "do not cross that line". There are many ways a coral may be able show his dislike for a neighboring coral, and they differ from coral to coral based on their abilities. One way is by extending long tentacles, commonly referred to as "Fighting Polyps", which are much longer (up to 4 or 5 times) than their normal "Sweeper" Tentacles. The Fighting Polyps contain a lot more nematocysts cells(stinging cells) which are used to inject toxins and ward off or harm other corals. Some corals have the ability to secrete a mucus composed of nematocysts cells, which they release during the night as a pre-defensive measure. These clumps of mucus can roll via the current and harm any corals that it may encounter. If a coral is exposed to enough of this mucus it will eventually kill it. Other corals can even release a substance making it difficult for any larva of other corals to be able to survive in the neighboring area. Or some corals can even release a poison into the water to defend its home area. Typically, most corals will not harm their fish tank mates , but a fish may provoke a defensive response from the coral, if they irritate it enough.