The flow control apparatus has first to eleventh channels, wherein the first to fifth channels are respectively provided in a first flow controlling body of a first flow controlling element. The ninth to eleventh channels are respectively provided in a second flow controlling body of a second flow controlling element. The first to fifth channels are extended downwardly from a first flow controlling side of the first flow controlling element. The ninth channel is extended upwardly from a second controlling side of a bottom end of the second flow controlling body and extended from the second middle portion of the bottom end of the second flow controlling body to the second edge portion and defines a ninth opening communicated with an outer space thereof. The tenth and eleventh channels are extended upwardly from the second flow controlling side of the bottom end of the second flow controlling body.