Well that makes it a little easier to make a choice both are about the same price however one pumps more then the other and uses more electricity. Does any one know if the RC head loss calculator is right or wrong I have looked at it with the same specs and changes the pipe size from 1" to 1.25" and the head pressure drops from 6 to 2.75. I connot see how just a little bit of difference can make that mush difference in head.

Would one one 1.25" bulkhead allow enough water flow to the pump. Both the 50PX-X and Quiet One are 1"MPTX1"MPT inlet/outlet. I will also be drilling a 1.25" return bulkhead to the loop inside teed down to 3/4" for a diffussed flow may have to put 1/2" bushings if this does not work the way I want it to.