Clownfish and Anemones have an incredible symbiotic ("living together") relationship rarely duplicated in Nature. These fish are commonly found swimming amongst the tentacles of both large and small Anemones at spectacular coral reefs. The reason Clownfish are not found at deeper depths is because of the dependence of the Anemone to be in water shallow enough to feed the zooxanthellae within its tentacles.Anemones have algae-like creatures that live within their tentacles that act as a food source for the invertebrate. These same tentacles that are beautiful and flowing are also deadly. The little poison darts that reside within the tentacles of the Anemone are called nematocysts. The Anemone uses their tentacles to stun and capture their prey. Amazingly, living within those stunning tentacles is usually where you'll find a majestic Clownfish holding down the fort. But how could these little creatures possibly withstand the powerful punch of an Anemone's sting? Many theories have been debated over the years since the discovery of this amazing relationship, but the theory most commonly accepted is that Clownfish build up a protective mucus covering on their scales that prevent the Anemone from being able to sting them. This may be accomplished in one of two ways: by the Clownfish absorbing the Anemones own protective mucus, which the Anemone uses to prevent from stinging its own body, or it may be that the Clownfish produces its own reactive mucus to the sting of the Anemone.Clownfish have a very distinct swimming motion that is different from most fish. This is likely passed on through their genetic makeup from centuries of wiggling within the tentacles of Anemones. As the Clownfish wiggles within the stinging tentacles the Anemone's mucus is likely smeared over the Clownfish's body, which then protects it from additional stings. The reason that this theory is believed over others is the necessity of the Clownfish to re-acclimate itself after it has been away from the Anemone for an extended period of time. When returning to the Anemone it then has to acclimate itself again or else it will be stung.This protective mucus covering, whether removed from the Anemone's tentacles or produced by the Clown itself, allows the Clownfish to stay within the Anemone which in turn gives the Clownfish protection from predators. Likewise, Clownfish are known for their territorial and protective nature of guarding the Anemones from any approaching predators. The little Clownfish will fight off intruders to protect its home at all costs. They will dart out from the tentacles to nip at the intruder and then shoot back into the Anemone for protection. Butterflyfish at the reef are very interested in eating the Anemone and the Clownfish will fight off even the largest Butterfly that approaches. Clownfish will also feed the Anemone with food it has captured in the water. These incredibly beautiful and intriguing fish are commonly orange, red, or pink with head or body stripes of white.These fish are the most common to be aquacultured in the United States. In the wild they live in small groups with one large dominant female, one smaller sexually active male, and a handful of smaller males and juveniles. When the female is lost the largest male will then change sex and become the dominant female with the other Clowns moving up the ladder behind it.