12 Volt Man;1894443; said:air pumps are mainly for decoration only or used to drive bubble powered ornaments.
with normal filtration, they are not needed for dissolved oxygen.
I agree. i only have an air pump on my tropical tank which pumps my 4ft bubble curtain. For visual effects only. It's a $10 air pump from Wal-mart and has 2 air outlets. cheap and does the job very well. Powerful enough to create a full curtain all the way across the 4ft tank. i have no air on my 120g and will have no air on the 180 I'm getting this weekend.