More bubbles = More Oxygen to the roots... More O2 = healthier plant. It's almost mandatory with the aerogarden, seriously. I have two 4 inch airstones in mine each with their own air pump. Get one in there soon, you won't regret it. Also, incase you havn't already, make sure all your grow holes are covered, don't want any light getting in there. It's a rookie mistake that will lead to root rotI am new to the growing scene and have purchased an aerogarden and my plants are looking fab but i have seen on a couple of sites that i will need a airstone as well. Why is this?