Heyo, people! I had a question.
I not-so-recently discovered [i.e., read about] the joys of sponge filters in the "Sponge Filters: Why and How"
thread. But, I couldn't understand why they needed air pumps to work. I understand the air line goes into the plastic tubing and "pushes" the water out, but without the tubing, wouldn't the water just be moved out on it's own?
Or, is it that the air pump aids in sucking up water to be filtered by the sponge?
Would a sponge filter work without a pump?
If someone could please explain the mechanisms of a sponge filter to this middle schooler, that'd be swell.