Bak Pak airstone mod pump

[gparr]

I'm trying to do the airstone modification to my Bak Pak. I bought a Coralife limewood airstone but am not sure how big of an air pump I need to drive the stone. What air pump are people using?
Gary

 

[Len]

I used to use a Corallife Luft Air pump when I did the mod years ago. It's adjustable so I could fine tune the foaming. I recommend an adjustable pump since exact air volume will differ depending on many variables.