Grow Mediums Dissolved oxygen directly affects root health, product quality DWC canna

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Might be interesting for a few hydro canna growers, totally meaningless for canna dirt farmers.

Dissolved Oxygen for Better Growth: Part II: Effects of Root Oxygen Starvation, Methods of DO Production, and Effective Aeration and Nutrient Delivery https://www.questclimate.com/dissolved-oxygen-better-growth-part-ii-effects-root-oxygen-starvation-methods-production-effective-aeration-nutrient-delivery/

Root oxygen starvation
Without adequate oxygen, roots become less permeable and can no longer absorb nutrients or water effectively. If left as is, plants begin to starve. This can mean stunted growth and even plant death.

You control how much DO the roots get

In your grow room’s hydroponic system, you’ll be controlling how much oxygen your plant roots get. They need from 7 to 10 PPM. (The water you use should be as pure as possible before your nutrient addition; the purer the water, the more DO it can hold.)

Do Not Use Hydrogen Peroxide (H2O2) to increase DO


I list this first because this is one of the most commonly used methods of DO production but it is NOT suitable for your plants’ DO needs. Here’s why: Hydrogen peroxide (H2O2) has an extra oxygen atom vs. water (H2O). H2O2 converts to water (H2O) plus an oxygen atom with a negative charge (O2-). That O2– atom is a free radical that will indiscriminately damage healthy plant tissue. Stay away from hydrogen peroxide, and instead opt for the method below.

[H2O2 is a great disinfectant for killing microbes]

Thinking out of the box a moment… oxygen, air – what’s the difference in these 2 words, these 2 gases?

Never be confused – Oxygen (O2 is always a pure gas. Air is always composed of a mixture of several pure gases, 80% of air is pure nitrogen gas… now that is really confusing for many folks!
  1. Low DO Saturation is a common precursor to sick roots, root suffocation and root death in DWC, RDWC hydroponic canna grows

  2. High volume air pumps never insure more oxygen

  3. 2 air pumps do not pump twice as much oxygen, that's sad too

  4. Minimal safe oxygenation is often limited by air, which is often misidentified and mislabeled as simply - oxygen

  5. The best way to correct a low DO problem in water is to dissolve supplemental oxygen gas (O2) or oxygen greater than 21% O2

  6. The best way to find out if you have a low DO problem is to actually test the DO inside the root ball – that’s a no-brainer

  7. Hypothermia is not the best way to correct a low DO problem

  8. Root suffocation, root death and decay always invites mass fungal colonization

  9. What hydroponic water reserve DO is considered “minimal safe DO % Saturation
10. Suffocation caused by low to no oxygen is untenable and deadly for aerobic plants and animals


  1. Have you ever considered actually test your DO Sat in RDWC, DWC hydroponic canna-grows?

Water chiller salesmen and horticulture scientist all make the claim that maintaining continuous “safe DO” is really important, vitally important.

If minimal safe DO is really so important then why is testing DO so adamantly rejected by growers when minimal safe DO is so vital for canna root health, beneficial microbial health and efficient nutrient metabolism?

Confusing… Perhaps a paradox? Or just meaningless 1st year horticulture science, freshman drivel.
 
Is there a specified and reliable methodology to test/measure DO at the root ball? If it as simple as a device or probe, they should be selling them next to the hydro gear at the garden center. Also, is supplying a purer O2 mix through the pump going to cost more at the end of the grow than its worth? Because proper maintenance and a product like hydrogaurd works just fine.

I would assume it would just be easier to use the same type of device as live wells in bass boats- uses electrolysis to split H2O molecules of res water to generate DO. I don't know what a cylinder of O2 costs though.

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Is there a specified and reliable methodology to test/measure DO at the root ball?
...proper maintenance and a product like hydrogaurd works just fine.

I don't know what a cylinder of O2 costs though.

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Yes, actually any DO meter may be used to test DO in the heart of hydro canna-root balls, just depends on where the meter probe is placed. MAPP gas oxygen is a cheap O2 source. Jewelers use MAPP gas O2 all the time.

Are you a DWC/RDWC grower or no?

Hydroponic Horticulture Science claims that plants/root health is vitally important for a great harvest. Horticulture experts also claim that using the best nutrients and chemicals will fail to be metabolized efficiently when the reservoir water DO is low you know. (suffocation) Root suffocation has no good ending for aerobic canna-root balls or cats, mice and man.

Do you have any idea what the optimal DO is for a DWC/RDWC canna grow?

If you grow hydroponically and don’t really have a clear understand about DO, check this out: Understanding Dissolved Oxygen by Kurt Becker 1/29/2016 http://www.ballpublishing.com/GrowerTalks/ViewArticle.aspx?articleid=22058

If you don’t grow DWC/RDWC this article will be of no value to you.
 
I do grow using DWC and RDWC, but consider myself a newb. Not sure of optimum range, but more is better! No doubt that O2 deprivation kills, I know first hand! Curious if someone hasnt already tried this, as virtually every other facet has been manipulated indoors and out. CO2 enrichment, lights, ect.

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Tested for optimum DO content for canna life cycles, I mean. Surely, side by side tests have been run in commercial aquaponics setups, that data may lean toward an optimum range for other plant varieties...

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The Water Chillers Sales Pitch is popular and makes since… here’s the “HOOK.” Cold water holds more dissolved oxygen and lots of dissolved oxygen is the most vital element for all hydro-cannabis grows. You must to buy my water chiller if you really want to be successful.

All water chiller salesmen claim that 100% DO Saturation is the optimal DO number and that is based on an internet DO chart (ambient air /water temp). More than 100% DO Sat is even better, but the DO chart does not register DO Supersaturation (>100% DO Saturation) so that is impossible and cannot actually happen. At least not with any internet DO Chart.

Bro-science gurus make the same claim based and authenticated with internet DO charts. Seems they all use a thermometer and actually test water temperature then extrapolate DO Saturation using internet DO charts.

Have you ever heard of any canna-forum hydroponic growers that actually test DO with a DO Meter or chemical test strips?

As plants, roots and microbial colonies grow to maturity over months, even more oxygen (O2) is required to maintain 100% DO Saturation, that's simply math. More aerobic biomass requires more oxygen to insure optimal hydroponic growing conditions. Most hydro growers hope for healthy root balls and healthy beneficial microbes right?

Many hydro growers may use bigger air pumps or additional diffusers hoping additional aeration equipment will insure more oxygen for the greater mass of aerobes as they mature. The glaring problem is that regardless of how much ambient air pumped, 2,4,10 bubblers all the oxygen you can possibly deliver is only 21% O2. Growing at altitude increases the DO problems proportionally to elevations above sea level growing. Same oxygenation problems with San Diego playing football in Denver… ambient hypoxia. Watch those San Diego football players lined up on the bench breathing O2 with an O2 mask strapped to their face.

Great idea... a side by side test - using a real DO Meter or DO Test Strips. Not a water temperature thermometer.
 
Colder water can hold more DO, but should not be used as the guage for the concentration of DO in solution. I still feel the aeration through electrolysis or pumping enriched air would be better.

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Colder water can hold more DO, but should not be used as the guage for the concentration of DO in solution. I still feel the aeration through electrolysis or pumping enriched air would be better.

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Clarification please just to eliminate confusion - In your opinion, does "enriched [ambient] air" mean the same thing to you as "[oxygen] enriched [ambient] air?"

Question… In your opinion, if ambient air contains 20% oxygen, what is the O2% in oxygen enriched ambient air?


 
Meant just plain old canned pure O2. Pump that in instead of ambient air. Air is obviously a combination of several gasses and the one that counts in this situation is O2. If your worried your air stones arent getting your trees big enough, give em pure O2. I have a MONSTER four and a half foot tall Auto Northern Storm in DWC getting ambient air from the garage that is THRIVING and a full foot taller than the same strain next to it in coco/peat/perlite blend. Res temps are stable, not using a chiller, just megacrop and slf-100.

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And a 951 gph commercial air pump with 4 inch cylinder stone.

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