Sanitized Water Supply and Roots/Rhizosphere

Looking back through the different threads I've seen a few recommendations by fatman7574 in using bleach to ward off root rot.

https://www.rollitup.org/t/lucas-formula-recipe-from-scratch-really.268790/page-8 post #57
"A teaspoon equal 76 drops. So 1/4 teaspoon is 19 drops. 19 drops is good for 76 gallons at 0.5 ppm."

I think his math is off.

This is a simple concentration/volume problem.

Concentration1 x Volume1 = Concentration2 x Volume2

6% chlorinated bleach = 60,000 ppm
1/4 teaspoon = 0.000325521 gallons

So

0.000325521 gallons x 60,000 ppm = concentration2 ppm x 76 gallons

Solve for concentration 2 and you get 0.25ppm

A half teaspoon would be more appropriate for 76 gallons but a quarter teaspoon would be great for 38 gallons. Feel free to use this equation yourself. Your goal is to get to 0.5ppm chlorine which has traditionally been used in tap water. chloramine has also been used at the same level and is more stable but less of an oxidizer.

Chlorine vs. Chloramine

Chlorine will not last very long in water, and I suspect in an aeroponic system it would be quickly evaporated. It most certainly wont make it a week between reservoir changes. It may not even make it back to the reservoir after a single mist.

Chloramines can last for weeks and I feel are the preferred method to providing a sanitized water supply. They also wont evaporate readily and are safer to use in aeroponics for this reason.

To make your own chloramine of high purity.

-First buy some ammonium chloride.

-Take your typical 6% bleach and pour a half of cup into a measuring cup and put it in your freezer. It wont freeze unless it gets ~20 degrees F.

-Now take your ammonium chloride and dissolve 9 grams into a half cup of water in a separate container and put it in your freezer. This will freeze at ~22 degrees F so you want to stay above that.

You can take a seperate cup of just regular water and put that in the freezer too. When the cup of water is frozen you are ready to commence. Just take the two half cups pour them in a jar and shake vigorously for about 30 seconds to really mix it up good and throw them back in the freezer and in 15 minutes you have your solution. Throw the cup of frozen water in the sink to thaw.

I know this makes a lot more than you need, but the amounts are just easier to work with and very cheap. The EPA allows for monochloramine up to 4PPM and at best this produces monochloramine of 95% purity in a 6% solution so just dose as you would with regular bleach except only add it once at reservoir change. You may be able to keep this solution for a period of time but someone with a pool chlorine checker would have to check it everyday to see how long it is stable. It will last longest in an airtight jar in your freezer.

Don't use this if you're dumping waste water into a septic system because I don't know if it will kill all your beneficial bacteria.

Note: This is just my DIY take on a patent I read. The conditions aren't ideally like the ones listed but I imagine they are close enough. I.E. household bleach molarity is 0.705, pH is ~12-13 but we're not bringing the solutions to below their freezing points inside of a reactor and keeping them from freezing by keeping them moving. To bring them to -8 degrees C we would need to be using stronger concentrations.
http://www.google.com/patents/US7045659

Let me know if it works.

But wait, aren't chlorine and chloramines bad? Ed Rosenthal told me so!

-http://www.nature.com/scitable/knowledge/library/the-rhizosphere-roots-soil-and-67500617

If you read the whole article you find that the primary purpose of the rhizosphere is to form a symbiotic relationship between the plant and bacteria/fungus in which the plant gives off carbon and the bacteria/fungus make other nutrients more readily available to the plant and increase the nutrient uptake ability per area of root. This is why when growing in soil you don't want any chlorine/chloramine because it can kill the beneficial bacteria.

I'm not sure about other hydroponics but I've read in great detail about how aeroponics allows for easier nutrient/oxygen/water uptake than other growing methods and so a rhizosphere is unnecessary. In other hydroponic methods a rhizosphere may lend itself to root rot and or other reservoir infestations.

Plants don't live in sterile environment anywhere in nature, in fact, plants are much healthier when they have beneficial bacteria to help breakdown and absorb nutrients.

I apologize, a sterile environment is kind of a misnomer.

All the kings horses and all the kings men could not make an environment completely sterile outside of a lab and even then it's difficult (ever try taking tissue culture clones?)

At any given point in time, there is about 10lb of bacteria on your body and this bacteria is beneficial to you. You also, at any given time have a few very bad bacterium but due to the sheer number of good bacteria they are out competed almost all of the time and so die off. This is all despite you showering everyday, washing your hands several times a day, etc.

Now imagine if you only had a limited amount of wash water. If you were to wash your hands in a large body of water or just plain water you will likely be fine, humans did that for a long time before we had soap. However, if you only had a 5 gallon bucket of water and you kept washing your hands in it I imagine you would begin to see bacterial bloom very quickly. A small amount of chlorine, chloramine, or other disinfectant could keep their armies at bay enough to continue using the water for a longer period of time.

This is the same scenario at play here with home growers. While you're providing the ideal environment for your plant you're also providing an ideal environment for bacteria. If you inoculate your plants with good bacteria and continue to recycle that water you will run into problems very quickly. If you're using coco and add the bacteria at the planting medium and then run drain to waste this is not so much an issue. We're not so much "sterilizing" the roots or reservoir as just keeping any bacterial blooms at bay.

Now, so far as the symbiotic relationships goes,
"The observation that including leguminous plants in crop rotations results in better yields of non-legumes goes back many centuries to the Romans and Greeks. It was not until 1888, however, that Hellriegel and Wilfarth (188 definitively proved that the cause of the improved yield was from the conversion of atmospheric dinitrogen (N2(g)) into ammonia, a form usable by the plant, by rhizobium bacteria ...Mycorrhiza assist plants in obtaining water, phosphorus and other micronutrients (e.g., Zn and Cu) from the soil and in return receive sustenance (carbon) from the plant."

Both the fungus and bacteria provide a benefit to the plant when it is having difficulty obtaining nutrients. You the grower, especially if you're using an automated doser, are providing all the nutrients in a form the plant can already use as well as all the water.

In the case of aeroponics,
"The nebulizer created a very fine mist. This was very efficient and reduced water consumption up to 70%.
This effect is accomplished when a drop of water is so fine that an air bubble wraps it, maintaining it at
the same height as the roots, thus avoiding that this drop of water touches the floor and
making the process easier for the roots to absolve this liquid. The water in the pumps have
a nutrient solution prepared according to plant needs." -"Development of an Aeroponic System for Vegetable Production"
J.L. Reyesa, R. Montoya, C. Ledesma and R. Ramírez

So the bacteria aren't really needed and what we're trying to do is just keep them from blooming into a big mess as trying to kill them all would be futile and the small amount that are there probably do perform beneficial functions with the plant (we hope).

I just have to disagree because I run a very controlled grow and have documented huge differences in roots,plants ,and over all health between a res with h2o2 and chlorine verses a hydro res with the proper beneficial bacteria. I was even able to remove the 1\2hp chiller and circulation system I had because temps weren't an issue.

It appears I'm wrong about the bacteria. Thank you for correcting me and giving me the incentive to research this.
Yes Aeroponics will grow faster than soil no matter what but they will also grow better with inoculation.

"Aeroponics (a soilless plant culture method) was used to produce Acacia mangium saplings associated with arbuscular mycorrhiza (AM) fungi. The seedlings were first grown in multipots (from 2 to 6 wk old) where they were inoculated with Endorize, a commercial AM fungal inoculum. They were then either transferred to the aeroponic system, where they were supplied with nutrient mist to the roots at regular intervals, or to soil (Evershine, Singapore) where nutrients were supplied on a weekly basis. After 4 months, measurements were made shoot and root growth, root P content, leaf area, photosynthetic rate, chlorophyll content and fluorescence, and AM infection. Aeroponically grown seedlings performed better than soil grown seedlings in all respects, when seedlings were grown with or without mycorrhizal inoculation. For example, aeroponically grown saplings were twice as tall as those grown in soil, and showed twice the rate of mycorrhization (when inoculated). The results suggest that the aeroponic system is an innovative and appropriate technology which has the potential to produce large quantities of tree saplings associated with soil microorganisms (such as AM fungi) for reforestation of degraded land in the humid tropics."-Forest Ecology and Management Volume 122 Issue 3 p. 199-207

In fact Agrihouse actually sells a product to speed up this inoculation process. They are owned by Richard Stoner the famous NASA aeroponics guru.

http://www.agrihouse.com/secure/shop/item.aspx?itemid=17

When you look at the certified analysis it looks just like a limited fertilizer...but then take a look at the patent and...

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=/netahtml/PTO/search-bool.html&r=1&f=G&l=50&co1=AND&d=PTXT&s1=Beyond&s2=Agrihouse&OS=Beyond+AND+Agrihouse&RS=Beyond+AND+Agrihouse

It is designed to enhance the incorporation of nitrogen fixing bacteria into the root nodules by the use of lipo-chitooligosaccharide (LCO)s and flavonoids or chitins/chitosans.

Chitins and chitosans which make up the cell wall of fungi and insects in order to stimulate plant production of chitinases which which are enzymes that the plant produces to degrade chitin.

I guess it's kind of like how you can use talcum powder to get rid of ants.

You can also buy chitosan as a dietary supplement in 1000mg pills. Just dissolve 40 per liter for a chitosan foliar spray concentrate to help innoculate against insects and fungi. 2 tablespoons of concentrate to 1 gallon of spray. This is about Elexa-4PDB

flavonoids are the chemicals plants release to increase bacterial production of nod-factors, LCOs are then produced as a result. I don't know of any easily obtainable LCO's but flavonoids can be found pretty cheap and can be used at a concentration of 5 mg/L with the same dilution as the foilar spray.

The flavonoids can be added in addition to beneficial bacteria such as arbuscular mycorrhiza(AM). If you look at Dutch Master they say not to use any bacteria/fungi etc. for the same reasons I mentioned but the AM work themselves into the root system. Start seed or clone in a rapid rooter and inoculate with AM and a flavonoid water.

If you use bacteria/fungi in your reservoir what and how do you use it?