Chlorine and it's effects on Soil micro-organisms

[Allen Repashy]

Ok,

Not that I am studying fertilization and the availability of it to plants, I am learning the importance of micro-organisms in the uptake of nutrients. For example, things like phosphites are converted to phosphates by micro-organisms to make them available for uptake by plants..

And coming from an aquaculture background, I understand the nitrification process very well........ and something keeps sticking in my head....

Chlorine and Chloramines KILL microbacteria..... If soil bacteria is an important part of the process that makes nutrients available to plants, then aren't we killing bacteria every time we water them with chlorinated water? I mean that's what it is in the water for, and it does a really good job of it. Chloramines can last a week in standing water. Does anyone use activated carbon chambers for irrigation? It might be cost prohibitive on a commercial scale, but I am more interested in the theory here and small scale application.....

Actually, on a commercial scale, you could easily inject a solution of Sodium Thiosulfate or similar compounds just like any other formula and neutralize the water supply. the stuff is very inexpensive and has a safe tolerable range for fish.... for example, in a 10% solution, one drop will typically neutralize ten gallons of water. Im my math is correct, then one gallon of this would neutralize more than a half a million gallons of water! Or in a 1% solution, a gallon would cover 50,000+ gallons. The byproduct of Chloramine and Sodium Thiosulfate is Ammonia, and Salt (NaCl) so the amonia could be used as a contributor to the Nitrogen supply for the plant. here is a link of interest on the subject.

Ascorbic Acid and Sodium Ascorbate (Vitamin C) is also a very effective dechlorinator, but I do not have experience with it. If it is cost effective and stable, it could be a great option.... and could lower PH at the same time. Here is a link of interest

Another option would be a degassing tower, but then you would need to pressurize your water to pump it.

And last but not least, in my searches today on the subject I found that they are using UV to remove chlorine. LINK


Just a thought.... my head is too full of them!

[Matt Maggio]

I admire your enthusiasm on these subjects!

I think the amount of chlorine we're talking about would have negligible effects on soil microorganisms because chorine would rapidly bind to soil organic matter and react with humic acids. That's my first thought.

Second, I would expect a small amount of NaCl to form in the reaction with ST.

Third, from what I understand carbon filters are geared towards low flow situations.

Lastly, I'm not entirely sure how adding ST would jive with an acidification program. A lower pH should help convert the ammonia byproduct to usable ammonium. I'm curious as to whether acidifying the water could neuter the chlorine in some way.

Matt

[Allen Repashy]

Originally Posted by Matt Maggio

I admire your enthusiasm on these subjects!

I think the amount of chlorine we're talking about would have negligible effects on soil microorganisms because chorine would rapidly bind to soil organic matter and react with humic acids. That's my first thought.

Matt

I disagree with you on this one Matt, If we were talking about water soaking into soil in the ground, I could see some of the effect you mention, but when you take a four inch pot and soak it near instantly with tap water, especially if it is a organic free mix, there is nothing that is going to break down the chloramine with any speed. Chloramine will last more than a week in non areated standing water.

For example, ten or twenty minutes of tap water in an established aquarium will near sterilize all the nitrifying bacteria and it take a month for the bacteria that complete the ammonia-nitrite-nitrogen cycle to recover!

Originally Posted by Matt Maggio

Second, I would expect a small amount of NaCl to form in the reaction with ST.

Matt

Yes, it does.....around 1ppm I think. what effect would this have, as I don't have a clue.

2 Na2S2O3 + Cl2 ↔ Na2S4O6 + 2 NaCl

2Na2S2O3 + HOCl ↔ Na2S4O6 + NaCl + NaOH

If this was a factor, then sodium hydroxymethanesulfonate (HOCH2SO3Na) could be used.

NH2Cl + HOCH2SO3Na ↔ H2NCH2SO3Na + HOCl

HOCl + HOCH2SO3Na ↔ H2NCH2SO4Na + HCl

NH3 + HOCH2SO3Na ↔ H2NCH2SO3Na + H2O

This locks up ammonia though and I don't know if it could also lock up your Nitrogen sources in fertilizer also... Is the resulting aminomethanesulfonate going to break down into nitrogen?

Originally Posted by Matt Maggio

Third, from what I understand carbon filters are geared towards low flow situations.
Matt

Agreed

Originally Posted by Matt Maggio

Lastly, I'm not entirely sure how adding ST would jive with an acidification program. A lower pH should help convert the ammonia byproduct to usable ammonium. I'm curious as to whether acidifying the water could neuter the chlorine in some way.


Matt

Me too! I need more answers damnit!

I have always wondered why plants just do better in the ground than in pots no matter what you do, and have postulated that the lack of a good environment for microbacteria could be the culprit.... not just from something like chloramine, but other factors like the extreme temperature swings from a black pot sitting in the sun, and possibility of total dessication from lack of watering that could also kill the microorganisms

[Matt Maggio]

I disagree with you on this one Matt, If we were talking about water soaking into soil in the ground, I could see some of the effect you mention, but when you take a four inch pot and soak it near instantly with tap water, especially if it is a organic free mix, there is nothing that is going to break down the chloramine with any speed. Chloramine will last more than a week in non areated standing water.

For example, ten or twenty minutes of tap water in an established aquarium will near sterilize all the nitrifying bacteria and it take a month for the bacteria that complete the ammonia-nitrite-nitrogen cycle to recover!

Yeah, in a more hydroponic situation I'd be more concerned

Yes, it does.....around 1ppm I think. what effect would this have, as I don't have a clue.

2 Na2S2O3 + Cl2 ↔ Na2S4O6 + 2 NaCl

2Na2S2O3 + HOCl ↔ Na2S4O6 + NaCl + NaOH

If this was a factor, then sodium hydroxymethanesulfonate (HOCH2SO3Na) could be used.

NH2Cl + HOCH2SO3Na ↔ H2NCH2SO3Na + HOCl

HOCl + HOCH2SO3Na ↔ H2NCH2SO4Na + HCl

NH3 + HOCH2SO3Na ↔ H2NCH2SO3Na + H2O

This locks up ammonia though and I don't know if it could also lock up your Nitrogen sources in fertilizer also... Is the resulting aminomethanesulfonate going to break down into nitrogen?

Sounds like that Chloram-X stuff. Aminomethanesulfonate should undergo nitrification. Also, I read that Chloram-X is resistant to oxidizing agents, so perhaps potassium nitrate fertilizer would be compatible, although KNO3 is a base forming fert. I wouldn't worry too much about the tiny amounts of ammonium that could be locked up. With succulents, it's better to err on the side of less N.

Me too! I need more answers damnit!

Again, nice enthusiasm!

Matt

[iann]

The amount of chlorine-containing chemical in tapwater is tiny, enough to neutralise an odd random bacteria that might sneak in, but not enough to affect taste or make the water unhealthy for us. The amount of both soil and bacteria in a pot is huge by comparison. Without the buffering affect of soil, such as in an aquarium, there may well be a problem. It also isn't clear to what extent bacteria and archaeobacteria are active in typical "sterile" soil-less growing media in pots, with the majority of nitrogen possibly being supplied directly as nitrate to the plants. Maybe they are, maybe they aren't, or maybe they sometimes are and sometimes aren't. Possibly one benefit of rainwater is to both preserve and refresh bacterial in the pot.

P.S. I would think that the less sodium you apply to the soil, the better

[Allen Repashy]

Hello Ian,

Welcome to the forums and thanks for the informative posts you have made thus far..... Maybe you should make a post on the "Introduce Yourself" forum so we can learn a little about you!

[Matt Maggio]

There are many benefits to rainwater, in spite its tendency to arrive at whim. Has anybody practiced or seriously considered rainwater harvesting? I've tried it with 35 gal drums off my growing structure roofs, and have plans for an elaborate system someday when I move to a bigger piece of land.

I suppose that could be its own thread.

Matt

[Allen Repashy]

Ok,

So if we have a soil-less media and are growing out plants from seedling to 4" pots via a continuous feed regiment, and there is a concern that for various reasons covered earlier in the thread, we are not creating an optimum environment for nitrification, would it be the proper choice to use ammonium nitrate as our source of Nitrogen... So that the most usable form of nitrogen (nitrate) is immediately available and we are not depeding on the nitrification process to break down the ammonia into nitrate via the microorganisms in the media.
I understand that plants can absorb ammonia directly, but do believe the preferred nitrogen form is nitrate.

So Ammonium Nitrate? a combination of Urea and Ammonium Nitrate?
What is the best source of Nitrogen for a situation like this? What do hydroponic growers use? It seems constant feeding in a soil-less media is closer to hydroponic growing than growing in large pots, and organic media.

The local fertilizer formulator that I am talking to about my Avocados recommends CAN-17 which is 17% Nitrogen, over 2/3 of it Nitrate.... the main factor if this is that it provides 8.8% calcium.... important for crops, but I have no idea if it is of value to succulents. It says it can not be mixed with phosphate or sulfate fertilizer... so I guess you would have to alternate feeding with your P and K fertilizer? They also promote CAN 9 which is 95% Nitrate and 11% Calcium


reference

[Matt Maggio]

I like a higher proportion of nitrate to ammonium to avoid tampering with other efforts to alter pH. I'd have to review the breakdown for ammonium nitrate. My pH hovers in the mid 7's. If you have pH readings in the 8's , however, your acid concentrate may have to be so strong as to shorten the life of your injector equipment. Since ammonium is acid forming in the growing media and root zone, you may therefore consider more of a 50/50 blend. What happens is the processes of nitrification and plant uptake release more H+ ions into solution than the bicarbonate release from plants during uptake of NO3. In other words, it takes more nitrate to counteract the acidifying effects of ammonium.

I prefer to grow with a buffered lightweight blend of loam soil, coir, and pumice, so can't claim much practical experience with hydroponics. I will say a couple more things about ammonium. I opt for less because I've noticed poorer quality growth on succulents in association with its use relative to nitrate. In addition, I don't like the way ammonium volatilizes into ammonia gas, especially during high temperatures and high pH. This gas can actually kill many microorganisms

Urea rapidly hydrolyzes into ammonium and can lead to a burst of ammonia gas. I've killed the roots on some plants with that stuff. I don't see a real need for it. Might as well piss on your plants.

Have you looked into Grow More products? I'm looking into them now.



Matt

[Tim Harvey]

I'd prefer potassium or calcium nitrate, given a choice. Nice and soluble, and the former is also great for starting BBQs.

T

[Allen Repashy]

Ok,

So because of my limited knowledge, I have to ask about Calcium Nitrate. It appears it can not be used in a complete NPK formula, so how do you apply it? In a constant feed situation would you alternate between two different mixes, the other being primarily P and K? ..... Or do can it be mixed into one... I haven't found a NPK formula that uses it, and on the Tech Sheet it states:

To avoid the formation of insoluble
precipitates, do not mix with
phosphate or sulfate-containing
materials.

Can someone explain this to me?

[Tim Harvey]

Most calcium salts are insoluble, so as soon as you have another anion around (e.g. phosphate) the calcium falls out of solution. So yes, you'd apply it on its own and preferably with soft water.

Calcium nitrate is a good foliar feed - maybe not so relevant for many of the plants discussed here.

T