plumbing help!

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Here's a pic of the plumbing for my bean animal over flow. Used a knife valve, slip/slip but added unions on both sides. All my overflow piping is 1" bulkheads into 1-1/2" piping. I also added ball valves with unions on each return. My return lines are 1" into a 1" bulkhead then reduced to 3/4" locline. I added a check valve right at the pump on the return and get no back siphon from the DT into the sump.