I really like the Current Culture system and like you, I have also talked with the several salesmen at CC regarding oxygenation and found them to be clearly and totally fixated on electric air pumps, ambient air and mechanical aeration. Actually, ambient air (mechanical aeration) has serious aerobic oxygenating limitations in many fields when optimal, sustained oxygenation in needed acutely and over months when optimal continuous safe oxygenation a major goal for intensive DWC, RDWC canna growers, especially when growing at altitude in the mountains.
Feel free to ask any welder, jeweler, intensive fish farmer, live fish transporter (Federal, State, Private fish hatchery, aircraft pilot, MD, PA, RN, LPN (nurse), EMT or professional football ball player breathing pure O2 on the sidelines in Denver, they all use and depend on pure O2 gas when ambient air fails to provide minimal safe concentrations of O2, that is a fact and common practice… why’s that? Well, that’s because ambient air will not insure enough oxygen to prevent cellular oxygen deficit (low oxygen). Insufficient oxygenation (low O2) is a major health issue for all aerobic plants, animals and microbes. But, fungi love low oxygen environments and thrive there. No disrespect for the Current Culture salesmen’s opinions or confusion between mechanical ambient aeration and oxygenation. Their job is to sell their product and selling is what they do best.
Consider this: All RDWC, DWC cannabis rhizome biomass and microbial colony biomass increase proportionally toward plant and microbial colony maturity the aerobic oxygen demand during several months of the grow cycle also increases proportionally. The eco system required more oxygen (DO) and ambient is not a good substitutes for oxygen as air contains 80% nitrogen. If the total oxygen demand is not continuously provided for by the grower, an oxygen deficit will develop.
Low DO’s are often a shock discovery and always a surprise for the grower when recognized (sickly, dying, slimy, stinking decaying roots and beneficial microbes in DWC, RDWC canna grows). Many RDWC canna growers (even growers using the CC system, worry about low DO and root rot every day and always “hope” that ambient air will provide enough oxygen to prevent low DO insults and the pitiful results of a low-O2 crisis.
A little techy, but you might find this enlightening:
Understanding Dissolved Oxygen, by Kurt Becker, https://www.growertalks.com/Article/?articleid=22058