Currently running one in my reservoir for my tapwater and feed. I run another one in my bubble bucket.
http://www.walmart.com/ip/Aqua-Culture-Bubble-Aquarium-Stone-1-ct/10532630
http://www.walmart.com/ip/Aqua-Culture-20-60-Gallon-Double-Outlet-Aquarium-Air-Pump-1-ct/10532634
Not sure if what i am using is good enough or if more would help. The bubble bucket is ~5gal and the reservoir is 5 gal
http://www.walmart.com/ip/Aqua-Culture-Bubble-Aquarium-Stone-1-ct/10532630
http://www.walmart.com/ip/Aqua-Culture-20-60-Gallon-Double-Outlet-Aquarium-Air-Pump-1-ct/10532634
Not sure if what i am using is good enough or if more would help. The bubble bucket is ~5gal and the reservoir is 5 gal