Hey @JoeCrowe
I know you are busy, but in due time, might you have something to add?
Feel free to contradict anything here you see that is not up to snuff… 
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The only time I ever added a pesticide to my crop was end all for whiteflies. Never again.
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Man, I never had white flies on cannabis but had em on other things, them sucka’s are tough to get rid of no doubt…ugg!
All comments are welcome really…
If anyone would like to comment on what they use to keep Pythium at bay I would love to hear your real-world results.
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Pythium only attacks when the oxygen levels are low. I make sure the nutrient solution is at 18C. When you achieve saturation at that temperature, which is pretty easy, pythium won’t grow.
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Wow!
Cool we even got a pic.
Thanks a bunch for stopping in.
@JoeCrowe
Do you have any recommendations for Pythium prevention when you are forced to be in warm temperatures like cloners?
@OriginalDankmaster96 is dealing with this right now.
I was gonna suggest Chlorine but wanted to chat with you and check my notes.
I do my best not to spread misinformation if I can help it.
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This is a good place to learn more about oxygen saturation.
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Just delt with/dealing with root rot now. Tried running a sterile rez and it was nothing but problems.
Going back to beneficial bacteria ,great white, giving tribus a shot and I picked up some southern ag garden friendly fungicide. The ag garden looks to be just Bacillus amyloliquefaciens. While the tribus has that in higher concentration ,Bacillus pumilus , Bacillus subtilis.
I run rdwc with air pumped into 8 sites plus the rez. I want to ditch all the air pumps and put a Mister or drip ring on the 8 plant sites. My guess is that the water running through the clay will a. Create more Dissolved oxygen as it drips through and rain drops onto the water surface b. It will help the beneficial bacteria get established in the clay and roots in the clay.
Cliff notes more beneficial bacteria, top feed water to create more DO.
Suggestions or solutions welcome.
Nice read.
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Ha that’s ironic, I used to use beneficial bacteria (southern ag friendly fungicide) in my cloning reservoirs, but after 2 bouts of root rot with high temperatures this summer I switched to a calcium hypochlorite solution (1g/gal of water) treated every 3 days at 6ml/gal. Have never seen roots this white and thick, cuts seem to root faster.
Notably I dont run DWC and this is only for cloning purposes. Found that the bio-film build up from the beneficial bacteria was ultimately a pain in the ass to clean every cycle. I wanted to stay organic and avoid chlorine at all costs, aint that just the way though.
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Lol that is funny, hey it ain’t one size fits all. I am not sure what you are describing as bio film but GW stains things brownish and leave a a residue in the bottom of the tanks.
I used hth pool shock and I believe the biggest problem was accurately dosing the system. It’s 8, 13 gallon sites and a 13 gallon rez 117 gallons. But here is the trick it’s never full. So accurately knowing how much water is in the system is tricky and in my experience dosing needs to be spot on. The cloner I use in easier to do and is only 3 gallons.
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Thanks a lot @shag . I planned on finishing a book today. Maybe tomorrow. Seriously. Thanks for sharing.
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Your work as a student is never done @crownpoodle now get back to work.
BTW
How are you feeling these days?..Better I hope?
Peace
Shag
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Thanks for an informative and cordial thread @shag!
I especially appreciated this comment:
“The surface level of the water is called the meniscus and it has been demonstrated that about 90% of the dissolved oxygen, known as DO, in a system is introduced at this point.”
I’m experimenting with those micro octopots and part of their magic is the oxygen transfer at the air/water gap in the reservoir. It seems to provide adequate O2 to the roots without air stones, pumps etc.
Regards,
-Grouchy
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Thanks @GrouchyOldMan 
I have done real-world experiments with a DO meter myself and air stones are not needed.
Some graphs to chew on.
Circulation pump is a needlewheel. Air injection prior to needlewheel. Several different states evaluated including air injected, no-air injected, pump low, pump high, and stagnant. Fill with oxygenated tap water at ~time zero. Left axis is DO saturation percentage. Right axis is temperature (purple trace).
DO saturation decreases with increasing temperature but is not immediate:
With a chiller:
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Yes the water doesn’t like to hold the O2 when she gets warm. You can run your system through refrigerator and keep it cool when hot. Johnson controls with high low temps can circulate water till hits sweet spot. I usually grow outside when getting too hot but things be a changing brother so yes good tech. I thought it was about pythium spread and I always keep an eye on it. Change out water in system 2 weeks and helps keep track of consumption and average VPD so kinda have to adjust feed for high heat and lower EC where I am at. Keeping water cooler definitely makes more manageable.
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What about hydrogen peroxide?
This will eliminate and prevent pythium, fusarium, and all the other pathogens.
Peroxide makes toxic pathogens more toxic, like BMAA.
Beneficials are better than ‘sterile’ as pathogens occupy a sterile environment far quicker than benevolent microbes. And PNSB eats pathogens.
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Think this is probably ok for the P-Crud.
Agral 90 or
I think they say the maximum O2 at 68 degrees is around 10-15 ppm but I suppose it depends on elevation, air pressure, mode of delivery.
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