The thing of it is, is that you don't need all sorts of extra O2 in the water to grow huge plants. I used to grow just fine with one 12" airstone in each tub but started using two a decade ago with no noticeable increase in growth or productivity.
While true that at any altitude the O2 percent remains the same the ambient air pressure is much lower and makes it hard for lungs to absorb it so less is delivered to starving muscles trying to surmount peaks like these. I took this pic a couple days ago on the drive back from Kelowna, BC.
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The only way to get big O2 increases in your nutrient soln's is to supply a higher percentage of O2 to the air pump to displace some of the almost 80% nitrogen that makes up our atmosphere. This is something I plan to experiment with soon by adding O2 to my air pump feed so the bubbles in my tubs is more like 50/50. N2/O2. That will definitely increase the percent of O2 in the water. The roots can't utilize N so why not get rid of some and replace it with extra O2.
As O2 is a powerful oxidizer too much could fry tender root hairs so it will be interesting to see what happens.
The Old Med is quiet, educated and the brightest on this block that I see, (no disrespect toward The Rocketman and his small band of brothers).
The Old Med knows about the profound effect of gas partial pressures (Henry’s Law) and has probably applied the gas law many times in his life. He also know that the partial pressure of O2 in air at sea level is only 159 mm/hg. I also bet he knows that increasing the partial pressure of O2 (the molecular driving pressure of the O2 molecule that is responsible for moving the molecule of O2 from point A to point B, commonly called simply “gas diffusion”). Increasing the partial pressure of O2 up to 300 mm/hg can be done easily by adding an additional 19% O2 to air increasing the concentration of oxygen from 21% up to 40% oxygen. This is commonly done when the biological oxygen demand in the res life support system exceeds the oxygenating limitations of ambient air (air pumps, air bubblers or water falls). When the collective root mas becomes massive and benny colonies are thriving and growing, at a point all the aerobes may need more oxygen to remain within the “safe” DO range within the life support system. Need more O2, just increase the partial pressure of the oxygen, that’s all there is to it and so simple and easy to do.
You certainly do not need an O2Grow machine to do this. By the way, again 1 more time Rocketman… I am not affiliated with the O2Grow Company in any way, nor do I own it. I have never been associated with the company contrary to the Rockets and his flock’s beliefs or false promotions that I am part of the company, Rocketman is no more than a common street liar.
I am quite impressed elemental O2 gas and how people can manipulate the concentrations within a life support systems DWC res system to guarantee the prevention of the dreaded low oxygen crisis, frank hypoxia, the predictable aerobic suffocation, root death ad decay that (root rot) that is requires for fungal outbreaks to happen.
I like the Old Med,
he’s not vulgar, he’s savvy and he knows that if and when his root mass and microbial mass in his res grow and exceed the oxygen demands of all the roots and all the benny’s collectively, that’s a big problem when his oxygen supply is limited by using air. When that happens the sickness, dying and death begins because there is insufficient O2 for everything is his life support system and results are imminent. He has probably paid close attention, took good growing notes over years of trial and error and learned not to overstock his life support res system. He understands the oxygenating limitations of environmental air. Not unlike a welder knows that his torch will not cut iron or steel when using high pressure compressed air to fuel his torch, eh?
Oxygen gas is a powerful oxidizer when the O2 gas comes in direct contact with iron or delicate organic tissue for extended periods of time. Tiny micro oxygen bubbles in res water that imbeds in root balls or direct contact with microbes’ delicate cells can certainly be toxic, very corrosive actually causing chemical burns/tissue mortality. On the other hand dissolved oxygen in water is for less corrosive than direct gas contact with pure O2.
High DO supersaturation in res water is not the point at all and is unnecessary. I cannot think of any reason why for high DO supersaturation. Effervescence is for Alka-Seltzer and Champaign hot beer when you pop the top. High DO super-saturation is certainly not for DWC res water for any reason I can think of other than just wasting O2 for nothing or, maybe the O2 gas bubbles used for protein skimming if there is a lot of decaying organic matter and debris in the res water.
Plenty of dissolved oxygen in DWC res water simply means staying with the “safe” DO range continuously 24/7 for the duration of the growing season, that’s all that is necessary when minimal safe DO is the point of the exercise. Plant roots and microbes are usually quiet healthy if the grower maintains the DO within the “safe” DO range for the drop season. After all, the grower is in control of the artificial life support environment, right? And, you also know that things can and often do go real bad, real quick when the grower loses control of the life support environment in a DWC/RDWC grow you know. Root rot is discovered 1 morning! Electricity went off, air pump failed, roots suffocated.
Things go real bad real quickly when any DWC grower fails or loses control of the life support systems environment. Plant roots die, microbes die, the fungi thrive and the crop fails or becomes irreparably damaged and harmed negatively affecting the harvest volume and quality of the buds that might survive this crisis. If you have ever had a dose of the root rot along with a fungal infestation, then you know the routine. It's worse than a dose of clap.
The incessant problem is the collective low oxygen insults and hours of hypoxia during the growing season that suffocate the roots and killed the beneficial microbes. Suffocation (hypoxia) resulting in sick, dying, dead and decayed organic material. Then fungal outbreaks can be predicted and should be expected. Hypoxic cell death happens in seconds and minutes, not hours, days or weeks. And the grower is scratching his sphincter making up excuses why this happened to his crop, does this sound familiar?
More root mass + larger beneficial microbial colonies always require more O2 to be healthy and normal, be in the "safe" DO zone. If a grower fails or choses to provide insufficient DO saturations and a low O2 crisis results for any reason, the low O2 crisis is always the same… sickness, death, decay and fungal outbreaks. Low O2 insults are the same deal for people too.
Of course this never happens to a savvy hobby grower (like the Rocket), eh Rocket?
Growers claim they never worry about root rot or fungal outbreaks because it never happens to them, right?
The point of insuring minimal “safe” oxygenation is the same for all strict aerobes, plants, animals, people, and oxygen loving microbes. If the grower cannot, will not, refuses to absolutely insure a continuous supply of O2 within the “safe” DO concentration range and there is not enough O2 available for all the rhizome mas and microbial colonies, the low oxygen crisis and result is always predictable.
It is clear to me that the vast majority of hobbyist are not interested in low oxygen crisis prevention or being pro-active, but always waiting for the low O2 crisis to happen, being reactive and routinely wait until they see roots dying and rotting or actually smell death in the grow room before the crisis mode is activated. Then, as usual, the race is on for the “cure” to kill the fungi (considered the “culprits” that always consolidate to feast the rotting roots, thieve and multiply, that's right eh?
If the rhizomes are healthy and thriving in a safe environment, there is nothing for the fungi to eat and no fungi infestation. The ubiquitous fungal colonies in the res water remain in check and fail to thrive. Healthy roots that are not suffocated are the best prevention for uncontrolled fungal outbreaks. Keep the DO within the “safe” range, that easy and a very a simple thing to do. Keep the plants healthy and the roots will thrive and be healthy too.
How simple can it be?