If your only growing five plants in your ebb and flow hydroton is a great way to go. YOu can save some cash by only buying a 5 liter or so bag of it ( way easier to wash, washing out hydroton sucks and un washed will stain your tray) and filling special square pots that come with plenty of drain holes. They are available at most hydro stores this will also allow you to move the taller plants to the outside of your tray and spread out the light distribution more evenly.