Was the O18 water also extracted from a cascade of electrolysis cells? If so, was it extra low in deuterium? My understanding is that, at least during WWII, N

Was the O18 water also extracted from a cascade of electrolysis cells? If so, was it extra low in deuterium? My understanding is that, at least during WWII, Norway had a bunch of hydro power they used for electrolysis to produce hydrogen in order to produce ammonia via the Haber process. Deuterium is accelerated about half as strongly as regular hydrogen in the electrolysis cells. If you connect up your electrolysis cells in series, the small gradient in hydrogen isotopes you get across each cell accumulates across the cascade, and also the regular hydrogen leaves as a gas at a higher rate. At least that's my understanding, which would also imply the end of the cascade that's depleted of deuterium is also enriched in heavy oxygen isotopes.