White Ball Sponge
Picture was taken in June 2000.
Nikon Coolpix 950 digital camera, Tiffen +7 closeup lense, full flash

This is an unidentified white ball sponge common to most reef tanks. This one here pictured is growing the refugium area of my sump. All of these are new growth because the rock placed in the sump was very bare and had no visible life on it.

Unlike most sponges this odd species has the ability to move. It uses little thread like arm to pull and drag itself across the substrate. Over a 5 month period I observed this sponge and notices it has moved about 4 inches in that time.

You can see what looks like little sponge spores being released. The arms the spores are attached to look very much like the arms it uses to pull itself across the substrate.