The right pump size depends on factors like your water source depth, the distance water needs to travel, and your household's daily water usage, with smaller surface pumps suiting shallow wells or boosting household pressure, while submersible pumps handle deeper boreholes more effectively. Checking the flow rate, measured in litres per minute, and the pump's maximum lifting height helps match a pump to your specific water source and household needs. If unsure, consulting product specifications alongside guidance from a local technician helps avoid choosing an underpowered or oversized pump.