Do fish have air or water in their mouths? How does this work?

So I went and looked it up! It turns out that fish actually pull water through their mouths, which goes to their gills, where oxygen is extracted!


This is exciting! And it makes a whole lot more sense than wondering if fish would get water in their mouths whenever they opened them, or if they were constantly swallowing water all the time.

Nature you guys. *Shakes head* It's pretty cool.