Common Name: Sponges
Scientific Name: Porifera
Sponges are the simplest of multi-cellular animals. Sponges are covered with tiny pores which lead internally to a system of canals and eventually out to one or more larger holes. By filtering water the sponge feeds and grows, sponges are very effective filter feeders, since they are able to capture and eat particles as small as bacteria as well as much larger particles. There are many different types of sponges and they can be quite colorful. Sponges can be encrusting or free-standing, looking like soft tubes growing out of the rock. They are a beneficial addition to the ecosystem. Some high-end specimens are available in fish stores.
White sponges are the most common in the saltwater aquarium, here are some examples of sponges found by hobbyists:
Common Opinion: GOOD