It's a "glorified sump pump". No need for any "plumbing" knowledge....unless you plan to build your own....and even then, it's so minor, even I could prolly manage it.
Did you mean "have pump placed in the tub"?....just to clarify, cuz my friend has a Forever Stainless that has a "pump place" built into the tub. That's a teeny bit more complicated.
I love, love, love, my recirc (it's a 14 yr. old Hydrosurge). Biggest benefits for me are quickly SATURATING the big hairys and I have a sensitive well in a drought area. This sucker (purchased new for $1000.00 in 1996, not built by me.) has paid for itself over and over again.
In film editing lingo, R2-D2-the robot in Star Wars...means Reel 2, Dialogue 2.