I am going to set up a closed loop system on my 75 gallon using a Reefflo Snapper pump and an oceans motions super squirt. My question is the pump has a 2 in inlet and a 1.5 in outlet. Do i have to use a 2in bulkhead along with 2 in piping going to the pump and then what about the piping from the pump to the OMss? I have to take it from 1.5 in on the pump to 1 in on the OMss unit. I know since this is closed loop it will work off of pressure so what is the smallest i can make the bulkhead and pipe bring the water to the pump?