Sorry Larry, to many options available and not enough info to answer this question. Give us name/manufacture or link and someone might be able to track it down.
I think you may have that backwards. Water must travel through the membrane to be clean, so the offset output is the filtered water, and the centered output is waste.
I think you may have that backwards. Water must travel through the membrane to be clean, so the offset output is the filtered water, and the centered output is waste.