阿東&Tank P47-48六月份更新照片 Hi 阿東: How many external overflow box on the back of the tank? Could you post a close-up picture of the overflow box? One 1" drain pipe can handle 600-700 gallon (about 2500L) of water per hour. If you are running 10000L/hr pump, i.e. about 2500 G/hr, you will need...