The Purple Tube Sponge reproduces asexually and sexually, asexually meaning that it can reproduce offspring entirely on its own without a partner. Sexually meaning it uses sperm or eggs from another sponge to reproduce. When the Purple Tube Sponge reproduces sexually one sponge releases the sperm into the water where it then is carried into another sponge. The sponge that collects the sperm then fertilizes it and it becomes larvae. It asexually reproduces through a method called "budding" . When this happens the new sponge grows on the old one and then breaks free.