Nutrient Temperature - Oxygen and Pythium in Hydroponics

Nutrient Temperature - Oxygen and Pythium in Hydroponics
by Dr. Lynette Morgan, Courtesy of NA Greenhouse

http://www.simplyhydro.com/nutrient_temp.htm

The hydroponic nutrient solution is not just a mix of fertilizer salts and water… One of the most important of these is dissolved oxygen, which is vital for the health and strength of the root system as well as being necessary for nutrient uptake.

… the effect of temperature of the solution on the dissolved oxygen levels and on root respiration rates also needs to be taken into account. As the temperature of your nutrient solution increases, the ability of that solution to 'hold' dissolved oxygen decreases. For example, the oxygen content of a fully aerated solution at 10°C (50° F) is about 13ppm, but as the solution warms up to 20° C (68° F) the ability of the liquid to 'hold' oxygen drops to 9 - 10ppm, by the time the solution has reached 30° C (86° F), then it's only 7ppm.

QUESTION # 1: What is the real cause of Pythium fungal infestations (Root Rot disease) in hydroponics?

1. high nutrient water temperature > 68 F

2. low dissolved oxygen in the nutrient solution and root zone? 1-6 ppm

100% DO saturation at 68F–sea level barometric pressure- solute concentration 0 is 9.2 PPM WITH AIR (AERATION) 20% OXYGEN

Have any opinions and/or actual experiences with Pythium fungi infestations or other serious root diseases?

Cheers

J

Thanks. We all know this.

TWS said:

Thanks. We all know this.

Click to expand...

Your welcome TWS...
I'm really glad to hear that all of you know about this root rotting disease, If everybody knows about this disease I would sure appreciate some suggestions from everyone here.
What are the triggers that activate the outbreaks?
How do you avoid and prevent these growth triggers from going off?
If the growth triggers are not activated, are the outbreaks and negative results preventable?

But, If you carelessly activate the growth triggers that make the fungi grow like it's on steroids, then how do you kill this fungus when the growth is out of your control and spreading.

Are Pythium outbreaks preventable?
How do you stop and or kill this root rot fungus when it' thriving, really growing and multiplying?
Thanks
J

I have attached the DWC forums, start with the Heinsberg sticky.
In short high rez temps and low Do levels or one or the other . There are several ways to combat it or not get it at all.

https://www.rollitup.org/f/dwc-bubbleponics.92/

I find a couple drops of chlorine bleach will keep my rez sterile

Thanks a lot TWS, I posted there: pg 201 https://www.rollitup.org/t/dwc-root-slime-cure-aka-how-to-breed-beneficial-microbes.361430/page-201

J Henry said:

Thanks a lot TWS, I posted there: pg 201 https://www.rollitup.org/t/dwc-root-slime-cure-aka-how-to-breed-beneficial-microbes.361430/page-201

Click to expand...

No prob.
With out reading the thing again his rez temps include using Bennies. A sterile rez requires lower temps . 62-67 f.
There is a bunch of other good threads and info as far as sterile rezs and non sterile.
As a poster mentions above using bleach . There are also other things to use beside heinsbergs tea such as hydroguard,pondzyme and a few others.