When you see a pump head rateing is this for output length only or both
input and output length combined? Iwaki pumps are rated at a specific gph at
a 4' head. I have 3.5' from the sump to the pump and 4' on the output side
to my tank. is this considered a 7.5' head or does the head rateing only
apply to the output side? Could someone please explain this or maybe point
me to a site or equation to make it simple. Any advice would be greatly
appreciated.
thanks
G.