Backyard Aquaponics
A place to discuss aquaponics

Heh.
The "showerhead" concept that is something that was invented by S&S. They had spent a ton of money and energy on air compressors to oxygenate the fish tanks. Apparently, Senior Tom's 16-year-old daughter mentioned drilling some small holes in the end of a PVC terminator to create a "showerhead" effect. They soon found that was all the oxygenation they needed and ditched the air compressors.

OK, yeah I've seen that.

I never pay for or use added air unless temps get high or fish get big then I chuck in a trusty bubbler till I cull fish or bring temps down. Larger systems will have return waterfall aeration like the small ones, Joels design for aeration is niftier, and quieter.

Joel and S&S also use the "piston" method of air exchange through the grow beds for more oxygenation; but that's almost a side effect. I would think using an airstone would always be a good thing if you can afford it (energy more than airstones, which are cheap).