Hi Brookie, it all depends on what variety of plant you are going to grow. The fish will provide some fertilizer but there will be macro and micro nutrients missing. If you just want to keep a plant alive and not too worried about strong growth it should be ok without fertilizer if you do regular waterchanges. The light is the most important element for the plant. Because you dont have much wattage you really need to have at least one grow tube in there if you want the plant to survive.