Hi, Yes I use 1" pipe. I guess it would be easier for me to get the bigger pump like 70 than upgrade the pipesYou do not mention anything about the plumbing on the return pump. I am going to assume its 1" pipe, since that is what most people would have. If you find the 55 isn't enough, you may want to consider upsizing to 1 1/2" pipe (obviously you would need adapters on both ends). I have used PanWorld pumps on my basement sumps for decades (they last for decades unlike most of the disposables today). When I upsize to 1 1/2" flex from 1" I reliably see a 20% increase in flow. Something to keep in mind.