First, thanks for your interest, efforts and time, especially providing Biksa’s oxygenation piece.
Some general observations a year down the road:
Hashtag, a real fish farmer, is no doubt an expert when it comes to manipulating DO concentrations to achieve optimum safe oxygenation for his fish; he grows fish commercially for his living. He knows how to manipulate O2 tensions in fish tanks full of fish and nitrifying bacteria colonies by manipulating O2 tensions in Henry’s Law. He’s basically a real DO water quality expert.
He makes the DO in his fish tanks anything he chooses, 4 PPM DO, 10 PPM DO, 16 PPM, 20 PPM, 40 PPM, 80 PPM concentration, DO saturated, DO Supersaturated in fish tank water. He simply increase the ambient air O2 tension > 159 mm/hg to say 200 mm/hg or more which would automatically decreases the Nitrogen gas tension in air. He’s a wizard at manipulating DO in water without buying a water chiller and using cold water… behold a real wizard a DO wizard.
He grows and sells fish for a living and I’m sure he sells a pound of fish is far cheaper than a commercial canna-grower sells pound of his commercial pharmaceutical quality canna-buds.
He increases and maintains optimal DO concentrations and saturations continuously in his life support fish tanks insuring no low DO events for both his eco-system in his fish tanks. However he accomplished this magic, his continuous DO production must be cost effective per pound of fish he produces and sells at market price. He also knows that low O2 insults seriously harm his crop of fish which directly affects his income and families life style
I spent a few hours researching intensive fish farming techniques, specifically water quality and ideal dissolved oxygen requirements. I discovered that fish farmers do manipulate DO concentrations dramatically which is SOP, intensive recirculating fish farmers do this every day worldwide. This is not bro-science, this is steeped in aquaculture science, it’s common practice, common knowledge in the intensive fish farming industry and has been around for decades.
I read the article you posted, interesting. The nut of this oxygenation piece: “Once the pore spaces become depleted of O2 for a period and then coupled with warmer temperatures, rots and diminished uptake are sure to follow. Even though your plants aren’t showing root rot, it doesn’t mean that they are wasting a lot of their valuable energy fighting infections at the roots rather than growing faster; all simply due to a lower O2 level at the roots.”
The DO (elemental O2) is the common denominator that determines various degrees of what each grower considers and calls “success.” “Success” for most hobbyist is often defined by no more than pics of plants and growing a plant that contains enough THC to alter ones state of mind when buds and leaves are consumed. “To each his own,” so they say.
Licensed commercial pharmaceutical growers may grow crops for the cannabinoid canabadiol (CBD) purity/concentrations. Either way, for the commercial pharmacudical or hobby growers, the optimal health of the plant throughout the growing season is directly proportional to the health of the plant roots, Benny’s, ATP production and metabolism that are living within any hydroponic life support system.
The perception of success is important, but relative for every canna farming hobbyist. Even the gorilla farmer that plants a sack of canna-seeds in a National Forest or a Mexican desert and returns 9 months later to harvest and behold what he has grown is considered to be a relatively successful farmer if when only few seeds sprout and grow to near maturity.
The article: Dissolved Oxygen in Hydroponics, “Dissolved Oxygen in Hydroponics is that missing link to faster growth rates, healthier plants and even bigger yields.” Written by Erik Biksa - Erik is a co-founder of Grozine and the editor at Grozine Hydroponics Magazine.
No disrespect intended toward the writer, he writes for a living. His oxygenation infomercial begins setting the stage with the image of a water chiller with this ambiguous open ended caption: “A Chiller increases Dissolved Oxygen in Hydroponics for faster growth and healthier crops.” This writer recommends classic archaic mechanical aeration methods coupled with hypothermia to insure minimal safe oxygenation.
This oxygenation (DO) technique is always limited and seriously restricted by Mother Nature’s natural boundaries’ (Chemistry Laws), i.e. ambient air, O2 gas tension in ambient air and cold reservoir water temperature, water salinity, total aerobic biological oxygen demand (BOD) and so on…
But, ambient air is usually called/written as oxygen (elemental O2) and often considered to be – “FREE.” “Cheap” is only 1 click up from FREE… Free often trumps cheap if and when you’re on a recreational hobby grower’s budget which is understandable.
The writer has many factual references, but emphasizes that marginal DO control is achieved by chilling the reservoir water, hypothermia. The effect of hypothermia – the DO Concentration changes slightly more than 1.00 PPM for every 10 F change in water temperature… that is only 1/1,000,000.00 PPM.
“SO, where’s one of the easiest places to get more performance out of any combustion engine that also happens to be one of the most overlooked performance factors in most gardens?”
“Dissolved Oxygen in Hydroponics is that missing link to faster growth rates, healthier plants and even bigger yields.” “However, few “think O2” when contemplating what is propelling their garden forward in the hopes of achieving health yields.” [the article suggest that minimal safe oxygenation is dependent on water chillers, cold reservoir water, more ambient air and more air bubblers that are functional, new and not stopped up.]
Fact: “Just like in humans, O2 is critical for respiration-when plants actually use all the sugars they manufacture during light hours to grow, this mostly happens during the dark cycle. You can load your crops with carbs, but if they don’t have enough O2, that can become a limiting factor in how much of those carbs they can “burn” for growth. Oxygen availability in the root zone is highly critical for root health and nutrient uptake. In warm and wet conditions, oxygen levels are low because colder water holds much, much more water oxygen-as do the pore spaces around the roots when empty.”
Fact: “Once the pore spaces become depleted of O2 for a period and then coupled with warmer temperatures, rots and diminished uptake are sure to follow. Even though your plants aren’t showing root rot, it doesn’t mean that they are wasting a lot of their valuable energy fighting infections at the roots rather than growing faster; all simply due to a lower O2 level at the roots.”
*** “Typically 16 PPM (parts per million) of DO (dissolved oxygen) at the roots is considered very good.”
“Most healthy growing situations are probably half of that [or only 8 PPM DO concentration]. Double these amounts are possible with specialized technologies that actually dissolve O2 in solutions, rather than just bubble it through (diffusion).”
This hydroponic oxygenation piece is interesting and does contain a few important scientifically accurate facts, but the writer seriously limits his oxygenation recommendations when he fixates and promotes DO dependency bases solely on water chillers, cold water, hypothermia, 65 F water temperature, mechanical aeration, *ambient air and DO chart predictions. Ambient air O2 tension, water temperature and biological oxygen demand (BOD) being the limiting factors of dissolved oxygenation aquatic life support systems, i.e. intensive recirculating fish farming, aquaponics and hydroponic DWC, RDWC canna-life support systems.
At best with no aerobic plant roots or beneficial microbes in that water, ½ of the optimal 16 PPM DO is not available. That’s a 50% below optimal DO concentration in the water before any canna roots or aerobic Benny’s are added to the water in the hydroponic life support system. When the “grow” contains mature plants and mature microbial colonies ½ of that 8 PPM DO is consumed by the dual eco systems.
The biological oxygen consumption reduces the DO to <4 PPM DO considered a low oxygen crisis for fish and canna-culture.
In order for this writer to achieve the ideal or optimum DO concentration (16 PPM DO Concentration for a hydroponic canna-grow using ambient air, water chillers, cold water, hypothermia…. 26 F water temperature would be necessary to achieve 16 PPM DO with no canna-plant roots or aerobic microbial colonies living in that water consuming DO.
I do not think mature canna-roots and beneficial microbes would thrive well in that freezing cold water even though that water would be highly supersaturated (>200% DO Saturation) with dissolved oxygen.
It is clear that intensive fish farmers can and do manipulate DO concentration in fish tanks water full of fish and how they do that is cost effective because this practice is common worldwide. If this oxygenation was not cost effective, why would they do that and they sell fish commercially, not commercial canna-buds.
Just thinking out loud… any thoughts?