Spectacular Reef Aquariums from Around the World

In Volume One we featured some photographs of reef aquariums from around the world. This was a popular section of the book, so we decided to do it again in Volume Two. We were amused to discover that the appearance of reef tanks has markedly transformed in the few years since our first book was published. The trend lately is to have a reef aquarium full of small-polyped stony corals. Volume Two is about soft corals and anemones, so the aquarium photographs here tend to emphasize the wrong...

The Biology of Soft Corals

We must begin with a good definition of soft coral because the popular concept and literal meaning of the name are quite different from the actual definition. Taie soft corals all belong to the subclass Octocorallia. Like stony corals and anemones, the soft corals belong to the phylum Cnidaria and the class anthozoa. What distinguishes them is the number of tentacles on the polyps. All soft corals have eight tentacles on each polyp, hence the name Octocorallia. Exceptions to this rule only...