 
Pumps are rated either LPM (litres per minute), LPH (litres per hour) or gallons. The rate stated on the pump is calculated without any pipework connected to it.
Once you start adding pipework this then starts to reduce the output of the pump. Any vertical pipework is called Head of Water which significantly reduces the flow.
Also if you add any non-return valves you will need to increase the size of your pump to allow for pressure from the spring. Non-return valves may chatter if the pump rating is to low.
The enclosed chart shows a pump with no load or vertical pumping of 1000 gph as you can see once you require the pump to pump three feet up this reduces the flow to 900 gph.
Nine feet up reduces the flow to about 600 gph and at thirteen feet the pump fails to pump at all.
You should check the technical information of each pump to ensure you will get the required flow at the required height.
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