right.well heres the deal. i suggested this one pump because of its price, having to buy 7 pumps will cost more than one pump. try looking on ebay and see what u come up with.the brand name is hydro farm. the other thing u really need to be worried about is the heat from 7 pumps in one rez.your nutrient solution will heat up verry fast and cause mucho root rot. sooo i say this to help u avoid a ton of problems and u will auctually be saving money.