Unlike hard corals, the Nepthea Tree has no internal calcium carbonate skeleton, and that is why it is considered a soft coral. It is found as small calcareous plaques, named sclerites, which are present in the coral?s tissue. The Nepthea Tree is named because it features numerous branches spraying outwards from a main trunk and also looks like a tree. Some of the polyps have additional layers of sclerites and therefore do not have the ability to retract. The Nepthea Tree is also commonly known as Cauliflower, broccoli, or branch coral for its morphology. It is semi aggressive and needs ample space between itself and other neighboring corals. Some Nepthea Tree can even produce toxins which are harmful to the inhabitants. It is moderately difficult to maintain in the reef aquarium, and requires medium to high lighting combined with medium to strong water movement. The Nepthea Tree is considered a good choice for a beginner to intermediate aquarist. For continued good health, the Nepthea Tree needs some additional supplement of iodine, strontium and other traces of elements. Apart from regular feeding, the Nepthea Tree undergoes photosynthesis using zooxanthellae which dwells inside its tissue and manufactures food and provides nutrition. It is known for its bright colors that add a splash of vibrant colors in your tank.
Leather Corals live in the shallow waters of Tropical Seas & Oceans in all parts of the world, and inhabit Reef Slopes and Lagoons. Leathers will go through a phase when they shrink their Polyps, and secrete a layer of mucus on their body, to be shed later. The mucus coat prevents any algal growth on Leather Corals. Moderate flow must be provided to help them shed this mucus layer or it can suffocate the coral.Leather Corals are moderately hardy creatures, which make them interesting additions to your tank due to their unique fleshy body and colors, especially Browns and Grays. Leather Corals do not have an exoskeleton and their skin has a tough, leathery touch.These easy to care for corals are great for the beginner and do not require high lighting. They do need moderate light and moderate flow.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 a 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 cnidarias have tentacles with stinging cells that can shoot tiny poison darts into prey or 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. Cnidarias can be either 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 the Coral.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 Corals, especially Hard Corals, should not be placed within reach of another Coral.