I am looking to install a Pentair Whisperflo WFDS-28 or -6. I see it has a 2 inch female pipe thread on the suction. What is the best practice for the male fitting? It seems best to go up to 2 1/2 inch on the suction pipe. Do they make a 2 inch MPT to 2 1/2 slip coupling?
I think I saw on another thread a union fitting that might be nice. I have seen pros and cons to unions. The pro being flexibility to remove and the con being air leaks.
Also, what is the best material for this fitting? just PVC?
All comments are appreciated.