Sponges are very useful for your tank. They are biological filters, their bodies filter and
clean the water from your aquarium. Sponges are multi cellular creatures. Their entire body is a system of pores
which permit water flow through their body.
They come in many different colors, and sometimes they resemble corals. There are about 5.500
sponge species that have been described. Their scientific name is Phylum Porifera and they can grow up to 6ft in
height. There are three main classes of sponge:
Class Calcarea - these are marine sponges. This species of sponge is one of the most common
found in aquariums.
Hexactinellida – also known as glass sponge these are a marine species.
Demospongiae – this is the classic sponge. They are found in marine environments, brackish and
freshwater, and at all depths.
Sponges come in different shapes, colors and structures. They have a perforated body, with pores
through which they breathe, eat and excrete. Their shape can be conical, tubular, or cup shapped. They are found
all around the world, mostly in marine and warm waters. They attach themselves to rocks, reef or to the ocean
They feed on small organisms, plankton and bacteria that is found in the water. They filter the
water through their body. There are some sponge species that produce their own food, with the aid of
photosynthesis. Sponges can filter immense amounts of water every day. The cells with which they filter water are
about the size of our white blood cells.
When you add a sponge to your aquarium, remember they will need a water current so they can
feed. If they don’t have enough water flow they will reshape and move in order to adapt themselves to their water
condition. It is best to have a moderate water flow in your aquarium so that sponges can survive.
The light should not be too powerful, or too close to the sponge. They prefer little light. Also
be careful when transporting them to your tank as not to expose them to air as this will kill them.