To “sponge” off somebody is frowned upon. A lazy layabout comes to mind – someone who is not willing to pull their weight and has to rely on the work or gains of other people. I think this is a very unfair use of the word “sponge”. As sessile and inactive as they look, sponges rarely stop working if the conditions are suitable. In fact, they are continuously pumping water through their system at an incredible rate. They are capable of pumping a volume of water equal to their own body volume every 5 seconds!
So next time someone accuses you of “sponging”, don’t get offended – get angry. Angry that they used the term “sponge”. Then maybe show them the video below which, by the clever use of dye, reveals the hard work carried out by sponges everywhere.
Youtube clip uploaded by ProfessorZurawski