I install a Norwesco single union ball valve on the input and output of all of my pumps. This allows you to remove the pump for service without any tools or mess. This means that you will most likely do it more often.

If I need the pump to drive more than one thing I put a PVC manifold with a gate valve on each port to adjust the flow to that device.
(Click here for a picture of a pump with a ball valve installed.)

I use flexible PVC tubing for plumbing because it does not grow algae in it like clear tubing does. (Click here for a picture of the flex PVC.)

The best place to get the flexible PVC tubing and the glue for it is www.aquaticeco.com

The best place to buy gate valves is www.usplastic.com
(Click here for a picture of the gate valve.)

The Norwesco single union ball valves come from www.agri-supply.com
(Click here for a picture of the ball valve.)

They do not do e-commerce, so you have to call them at 1-800-345-0169 to order.

The part numbers are as follows: