Tank Problem -- Pump at the END? I will try to post more relevant data if possible but my main issue is this: I have a pump that receives water from a reservoir--so basically a gravity feed into an open-air tank. The tank itself is supposed to feed into a pump (that is located at the very bottom of the tank horizontally extending from it). I have never seen anything like this, it doesn't seem logical to have any sort of pump at the end of a reservoir when you could use a pump for just getting water into a tank and let gravity do the rest. There is no mention of whether or not the pump is connected directly to the thing and/or feeds into another tank for the pump or if it just stops inside some sort of pump and just goes out to the town. The paper literally says "The outflow of the tank is through a pump that pressurizes the distribution network throughout the town." I think I can figure out most of the problem, but the way to calculate outflow is confounding me right now. If it's a pump sucking out water, that's one thing--if it's just gravity feeding a pump, that's another thing.