Sponges

Sponges filter massive amounts of water every day, feeding on the microplankton. Many will develop calcium, silica or sponging structures to support their shape. Sponges need to be anchored in rockwork. The most critical concern is that sponges never be exposed to the air. If it is, the air would become trapped in the matrix of channels that line the inside of its body, blocking the path for planktonic food to reach its cells. This will result in death of the sponge.

Some sponges that come on live rock will survive and grow if the conditions are right. Sponges come in many colors and shapes and do best in low light situations.