If you have extra long air line just plug the end of it up and take a safety pin and poke holes in a straight line about 3-5 inches down the tube not all over in different places on the tube. Space the holes making them get closer together the closer you get to the plugged end of the tube. Test it to see if your getting good air bubbles about the size you would have from a air stone. If needed find something and make the holes a little bigger. Bury that in the bottom and your good to go.