Powerhead vs Air Pump?

I've decided to set up a secondary sponge filter in my 40 gallon tank. Can someone please explain the difference between a powerhead and air pump, and which one you believe is more beneficial? Evidently I need this put in layman's terms because I'm just not understanding. Thanks in advance!

 

An air pump supplies the aquarium it air via air stones. A power head is used for water circulation. Both are beneficial to have especially in a larger tank. Hope this helps!!

 

Is one better or more beneficial than the other? I'm only using a sponge filter as a means of extra filtration and to have extra filter media if I ever need it. Thanks!

 

Well they are both for different things. One is for air one is for circulating water. For a 40, circulation is not that necessary but an air pump is definitely good to have.

 

Powerheads move water around better than sponge filters do. Some powerheads have sponges on them, so they can serve as another filter. The nice thing about powerheads is that they can keep the water stirred up enough to keep particulate and gunk from settling on the bottom, so they can keep the tank cleaner. But it really depends on the stock of the tank and if they appreciate the extra flow.

 

Thank you! Seeing as it's only being used as a secondary filter and the real reason I'm setting it up is to have filter media to seed later, I think I'll just stick with an air pump. Thanks guys!