dude all you need for a bigger hydro system is trays, pvc pipe, and spaghetti pipe, set your trays on top of your rez and watch the water just run back down, voila brother you could run an infinite amount of plants like that, a $40 pump could prob feed at least 60 plants, maybe moreThe pump runs all day and night dont know the rocks. was easy system to use because it it like an ikea hydro setup so i dont have to find somone to build me one