To clean the pump, carefully remove the 4 screws on the front of the pump.
Gently pull the output housing off so that you do not damage the O-ring and set the housing off to the side.
Then, simply remove the impeller from the assembly and use warm soapy water to clean it and remove any debris. Rinse the impeller and output housing with clean water and then reassemble the pump.
Be careful to not over-tighten the assembly screws when you're putting everything back together.
Plug the pump back into your controller and you're ready to go again!