Instead of having the water return the tank, all you need to do is have a T piece in the feed from the tank to the pump, just before it goes into the pump, and another T piece in the delivery pipe from the pump, just after it exits the pump, then join the two T pieces with a short length of pipe and put your tap in the middle of this pipe. Then when you open the tap the water just circulates round the pump - no need for another long length of pipe back to the tank. You can put another T piece after the first one in the delivery side to split the water to two poles.