In shallow water where the temperature is at least 65°F and preferably 77°-84°F grow Sony corals only in clear sunlight. The average salinity of water is 36 ppt (point per thousand) that’s where they grow best, and there is little wave action or sedimentation from river runoff. The conditions above occur only in some tropical and subtropical areas. Most coral reefs are found in the Indo-Pacific region, which stretches from the Red Sea to the central Pacific. Around the Caribbean Sea smaller concentration of reef occurs. In addition to warm water reefs, knowledge is expanding about other corals that do not depend on sunlight, and form deep in cold water, these reefs are known as cold water reefs, and some of them are outside of the tropics.

Warm-water reef areas.
The conditions needed for the growth of warm-water coral reefs are found mainly within tropical Pacific, and Atlantic oceans. The reefs are chiefly in the western parts of these oceans, where the waters are warmer than in the eastern areas.

Lophelia Pertusa is one of a few of the reef-forming coral that grow in cold water, at depths to 1650ft. (500m).

Biotic includes all life forms living on the reef. A few are density of zooplankton, density of living coral polyps, population of fish, population of mollusks, population of echinoderms, and population of benthic crustacean.
There’s a lot of overfishing, reef risk. There disappearance would “hurt” there habitat. As there “taking over” other animals would be endangered by the risk under the living reef. Marine biology as discovered that living under the water isn’t as easy, even for the animals that live under the ocean, because the fish eat the other fish and there population is expands. The life under the ocean is becoming less colorful.

· Animals-Brittle star- The Brittle star is like the star fish, it is spiky, and as a hard shell, to protect it for harsh brutal (a.k.a. harmful stuff),are NOT fish
· Sea star- lives in the rocky floors of the ocean, is NOT a fish at all, and they also eat clams.
· Star fish- they slowly move among the rocky sea floor to move around are NOT fish, they are tiny, and they eat meat.
· Angel shark-they hide in the dark muddy sand part, by day they lay and sleep and hunt by night, slow swimmers, and they have wide fins that look like wings.
· Lemon shark- is a very dangerous to other living things in the ocean; they grow up to 12 feet long.
· Nurse shark- mostly lay among the bottom of the ocean floor, at night they hunt for fish like: lobster, squid, octopus, and other sea-bed animals.
· Sand shark- found in temperate and tropical oceans, lives in shallow parts of waters, the shallow shark rarely attacks people (a.k.a. swimmers)
· Blue ring octopus- lives in warm shallow parts of the water, blue rings all around its body, there life span is 11/12 years.
· Cephalopod- very fast swimmers, some have hard shells, they are meat eater they eat other fish.
· Cuttlefish- they have a soft body, also a very fast fish, they can change their skin color, there life span is 18 months
· Squid do not have backbone, relates to the octopus, they can also change their skin color, they hide from there predators, they squirt black dark ink.

Importance of Coral Reefs

The coral reef is important for many reasons. But the most important reason is they provide protection and shelter for many different species of fish. Fish would be homeless without coral reefs. They would have nowhere to go and nowhere to have their babies.
Reef fish and mollusks feed between 30 to 40 million people every year, they also increase the diversity of our world. They make beautiful pets and people make good money by catching and selling these animals. They provide many people with an income so that they can feed their families.
Corals are very important in controlling how much carbon dioxide is in the water. Earlier you read about how the coral polyp turns carbon dioxide in the water into a limestone wall. If we were without coral, the amount of carbon dioxide in the water would rise dramatically and that would affect all living things on Earth.
In addition, coral reefs are also very important because they protect from strong currents and waves by slowing down the water before it gets to shore. That’s why it is called barrier reefs. A barrier reef provides a barrier between the ocean and the shore.
Coral reefs are important for many reasons…… the coral reef has many different kinds of animals and plants that live there. This is called “biologically diverse.” This is also important, because just like the rainforest, coral reefs may be the source of medicines, chemicals or other resources that haven’t yet been discovered. We will never get a chance to discover these resources that we need, unless, we save these environments.

· Algae
o A diverse group of aquatic photosynthetic eukaryotic organisms that make up one of two subkingdoms in the traditional kingdom Protest. (The other subkingdom is Protozoa.) Newer classification schemes place some algae in their own kingdoms and others in the plant kingdom. There are many colors of algae red, green, and brown, etc…

· Barracuda
o A carnivorous fish usually found in tropical waters. There are about twenty species in the family Sphyraenidae. They are usually 1.2 to 1.8 m (4 to 6 feet) long, although some are much larger, notably the great barracuda of Caribbean and West Pacific waters. The family as a whole are aggressive feeders, with large mouths, many teeth, and a heavy under slung jaw

· Coral
o One of a group of animals belonging to the cnidarians class Entozoan. They secrete a hard calcareous skeleton and are important geologically in biostratigraphy and because of their reef-building activities

· Squid
A member of the large order Teuthoidea of marine mollusks of the class Cephalopoda. Squid have a long body, a distinct head, and 10 arms, two of which are much longer than the others. These are used as tentacles. All the arms have undersides covered with suction disks. These in turn are controlled by giant, and the whole is coordinated by a sizeable brain. The squid has exceptionally good eye-to-tentacle control. Like the octopus, it is teachable in an aquarium setting.Squid range in size from 1 cm (0.2 inches) to the giants, 20 m (66 feet) long.

· Zooplankton
Zooplankton are generally small, weakly swimming, nonphotosynthesizing organisms such as daphnia and copepods that move to and fro with tides and currents. Daphnia or water fleas are small freshwater crustaceans that eat algae and are forage for finfish such as trout. Copepods are also small crustaceans and a major component of the zooplankton community. Plankton are classified as synthesizing (phytoplankton) or nonsynthesizing (zooplankton) organisms rather than plants or animals because some phytoplankton are able to hunt for their food when photosynthetic activity is low, such as during periods of cloudy weather, when light levels are low. In common usage, however, phytoplankton usually refer to plant plankton, and zooplankton to animal plankton.
Zooplankton are found in both freshwater and saltwater environments. They are mostly microscopic heterotrophs, including bacteria, protozoans, and the larval stages of an assortment of larger animals.

· Phytoplankton
o The major photosynthesizing organisms in the open ocean. Many of the species are so small that they were uncollectible until the advent of truly fine nets. The nutrient requirements of these organisms are nitrates or other specific trace elements such as silicon for some others. The presence and quantity of the required materials and certainly temperature are the growth-limiting factors for phytoplankton most often the result of the nutrient-rich cold bottom water moving toward the surface euphotic zone. Cold core rings spun off major ocean currents will also provide a nutrient-rich region in which there will be a plank tonic bloom; in a warm current the bloom can occur at any time of the year. The ultimate controlling influence on the growth of the phytoplankton population is the population that feeds on it.

· Four Eyed Butterfly Fish
The Four-eyed Butterfly fish (Chaetopod cap stratus) is a butterfly fish (family Chaetodontidae). This species is found in the Western Atlantic from Massachusetts, USA and Bermuda to the West Indies and northern South America. Four-eyed butterflyfish are deep-bodied and laterally compressed, with a single dorsal fin and a small mouth with tiny, bristle like teeth. The body is light grey, sometimes with a yellowish hue, and dark forward-pointing chevrons. The ventral fins are yellow. The species gets its common name from a large dark spot on the rear portion of each side of the body. This spot is surrounded by a brilliant white ring, resembling an eye. A black vertical bar on the head runs through the true eye, making it hard to see.[1]
This pattern may result in a predator confusing the back end of the fish for the front end. The Four-eyed Butterfly fish’s first instinct when threatened is to flee, putting the false eye spot closer to the predator than the head. Most predators aim for the eyes, and this false eye spot tricks the predator into believing that the fish will flee tail first. When escape is not possible, a Four-eyed Butterfly fish will sometimes turn to face its aggressor, head lowered and spines fully erect, like a bull about to charge. This may serve to intimidate the other animal or may remind the predator that the butterfly fish is much too spiny to make a comfortable meal.
Four-eyed butterfly fish usually frequent shallow inshore waters, where they feed on a variety of invertebrates, mainly zoantharians, polychaete worms, gorgonians and tunicates. This fish is known for its uncanny ability to swim in and around coral heads and reefs. They are able to find their way through the most intricate passages by swimming on its side or even upside down. Like its relatives they mate for life and therefore they will often be seen in pairs.

· Purple Sea Urchin
An echinoderm (class Echinoidea), enclosed in a thin brittle shell covered with movable spines; it looks like a dark red, blue, or purple pincushion. The name is derived from the Greek for hedgehog. The sea urchin has been known for millennia and has left a fossil record since the Ordovician period, 500 million years ago.
urchin is a regular echinoid (symmetric) with a roughly globular aboral (top) and a flattened oral (bottom) surface. Its mouth is on the oral surface and is equipped with hard teeth. Almost all of the urchin is covered with a calcareous, spiny test, or shell. In addition to the spines, five sets of podia (feet) protrude from the test. The urchin moves using both its feet and its spines.
Urchins are ubiquitous in tropical and warm temperate waters. They are used as a food by many people and have a place in the lexicon of both French and Chinese cuisines. The sea urchin's eggs, which develop rapidly after external fertilization, are primary tools for embryologists; the development of the eggs is a "textbook" illustration of the staging of cell division

· Sponge
A marine animal (phylum Porifera) characterized by a porous structure and a skeleton of interlocking, thornlike fibers that may be calcareous (Calcarea), or siliceous (Hexactinellida), or protein structures (Demospongiae). The last is the largest group of sponges. There are about 9,000 known species of sponge of which 20 or so live in fresh water. Marine sponges range from intertidal ones to hadal ones living at depths 8,500 m (26,000 feet) below sea level. Their color can vary from pale yellow to orange, red, brown, green, and black. The glass sponges are found in deep water. These very pretty specimens, such as the Venus's flower baskets, are taken as collectors' items.
sponges are home to communities of mantis or snapping shrimp. These communities, like beehives, are all one family.

· Seaweed
A plant belonging to any one of several thousand species of multicellular marine algae may be described as seaweed. Some seaweed are large. Certain species of Macrocystis and Nereocystis, found in the Pacific and Southern Oceans, grow to more than 100 feet (30 m) in length.
Seaweeds comprise three plant phyla (or divisions), the Rhaeophyta (brown seaweeds), Rhodophyta (red seaweeds), and Chlorophyta (green seaweeds). Seaweeds grow in coastal waters throughout the world, from the uppermost part of the shore reached by spring tides to where the water is about 165 feet (50 m) deep. At greater depths there is insufficient light for photosynthesis

· Surgeonfish
There are over 80 species of surgeonfish worldwide and 25 of these varieties live in Hawaiian waters. Although they come in many different color variations, they all share the same basic structure. The name “surgeonfish” comes from their hard spines at the base of their tail. They have one spine on each side of their body that lies flat in a groove until the fish is provoked. In times of danger, a surgeonfish will flip its tail and the spines pop out like small knives. They resemble a surgeons’ scalpel, thus the name surgeonfish.
Surgeonfish are herbivores and reside in the shallow waters of the coral reef. They feed on algae, so look for them near rocks that get a lot of filtered sunlight. Depending on the variety of surgeonfish, you will find them grazing alone or in small groups. They do not typically form large schools but stick to small groupings

· Yellow Fin Grouper

The yellow fin grouper (Mycteroperca venenosa) is a coral reef fish native to the western Atlantic, Caribbean Sea, and Gulf of Mexico. It is generally a denizen of the deeper reef areas but it may venture into shallower waters, especially during the cooler seasons.
The fish is variable in color but is usually similar in appearance to the Black Grouper. It is distinguishable by the bright yellow trim on the pectoral fins. The yellow fin grouper is a hearty fish, often reaching 10 kilograms. It is considered quite tasty and is one of the more popular Gulf game fishes. It has been known to be a cause of ciguatera toxin poisoning, however. An attractive animal, the Yellow fin Grouper is a popular aquarium fish.
This species is one of the main catches in the fishing industry in Bermuda. It is considered overfished, and is currently threatened in several areas

· Nassau Grouper
o The Nassau grouper is a large, oblong fish native to the tropical western Atlantic Ocean. It can grow up to 4 ft (1.22 m) in length and can weigh up to 50 lbs (22.68 kg). Currently listed as a "species of concern" by the National Marine Fisheries Service (NMFS), the Nassau grouper was heavily fished throughout the 20th century and became commercially extinct in the U.S. Caribbean during the mid-1980s.

· Animals: The coral polyps-Hard and soft, hard corals that have an internal, rock-like, chalky skeleton that remains when they DIE!!
· The purple sea urchin-Is a small plant, that is spiky, lays among the rocky sea floor, shallows waters to great depths.
· Sea anemone-Sea anemone look like flowers, but they are predators animals, they have NO skeleton to them at all.
· Star fish-Are spiny hard-skinned animals that live on the rocky floor
· Brittle star-Brittle star is NOT a fish, but they are related to the well known sea star
· Clam-Clams are animals that burrow there self’s under the sea floor, they have 2 shells to protect their soft body’s.