Practical solutions to bicarbonates

[LaymanWayans]

I'm trying to better grasp lockout/deficiency issues and need to get a grasp on carbonates/bicarbonates in water before I go any further. Bear with me, I skipped Chemistry class.

Lets assume a tapwater, surface water or well water source contains the following:7-8pH, Calcium-65ppm, Magnesium-25ppm, Potassium-04ppm, Sodium-95ppm, Flouride-01ppm
Total ppm: >190ppm

What of this total is tied up as [bi]carbonate? All of it?

What effect would adding lime have on bicarbonate levels?

Is the total Ppm/TDS [of alkaline constituents] a direct measure of/correlation to water alkalinity, meaning a Ppm meter will guide me in my precipitation goal of 75-85% bicarbonate reduction?

Agricultural literature states the following acids are efficient at neutralizing bicarbonate: Hydrochloric, Phosphoric & Sulfuric. Does anyone have a rough estimate for application rates of these acids? And what would be the best way to readjust pH after treatment without adding alkalinity back in?


Does CO2 affect alkalinity of water or only pH? For those of you using rainwater, do you aerate your collections to reduce CO2?



I read lots of information that seems contradictory on the surface until deeper investigation. Such as "throw away your pH meter for organic growing", or Calcium Carbonate being a common organic amendment while plants cant use it and bacteria seem to produce it rather than take it apart. In chasing that rabbit, it seems I may have found the answer to my ultimate question:

Are root and fungal metabolites responsible for making Calcium Carbonate available in organic systems?

If that's the case, is the practical process of neutralizing bicarbonate on a small scale,say 20 gallons a day,as simple as adding citric acid (a metabolite of fungal colonies and cannabis roots) to my irrigation tanks,waiting 24hrs for the magic to happen, then readjusting pH as needed (,matching medium pH +/- 0.5 to limit root shock and microbial genocide?)? Would that explain why pH climbs so quickly after attempting to lower it with citric acid?


Are many growers shooting themselves in the foot by turning away from citric acid, as I did, having not properly understood alkalinity issues and seeing it as a poor choice for pH down?

 

[mexweed]

ph is the measurement of alkalinity/acidity

sodium bicarbonate is baking soda and it's a super weak base, compared to like sodium hydroxide

citric acid is a weak acid and doesn't hold a ph level for much more than 24 hours, ascorbic acid works much better

phosphoric, sulfuric, and hydrochloric acid are strong acids, most of the hydro shop ph down is phosphoric acid

there's acetic acid too (vinegar)

ascorbic acid can help neutralize chloramine and is just vitamin c powder vs some bottle with chemical burns and poisoning warnings on it

but if you're trying to hold a certain ph for a large volume of stored water, the hydro shop stuff is what you want

 

[LaymanWayans]

I've been told alkalinity and pH aren't the same but it looks like that's saying speed and mph aren't the same. PH does measure the ultimate effect of alkalinity, it just doesn't measure how much acid would be required to counteract the bicarbonates,etc. Obviously more bicarbonates require more acid. I'm going to try some experiments, I just need a reliable PPM/PH combo meter with a storage cap that actually stays on (why, Apera, why? )

The more I try to get a grasp on this, the more confused I get. I have serious tap water issues (16gpg, or 275ppm) and horrible math/science abilities on top of that. I finally understand why so many people on city water use RO water and bottled Calmag/micronutrients. Silly me thought chlorine and fluoride removal would be enough (works for humans) .

The biggest question on my mind is how to reduce alkalinity to practically nothing while keeping ph in range. The only option I'm aware of is aeration,and trial+error.

One publication says the zero point of alkalinity is 4.3 (while another website says 5.5 will reduce alkalinity to zero? And yet an other states that 6.5 will reduce alkalinity by 50%) . Well I tried pHing as low as possible and it crept below 5.5 and had deficiencies. I pHed the next run to 7 and had deficiencies. Running LEDs seems to compound the problem.

The 2nd biggest question on my mind is still, why is calcium carbonate a good organic soil amendment, but is a bad water contaminant? I really don't want to use RO.


After I sort all this out, I'm writing a book: Urban Gardening for Dummies, because even though I'm a dummy I know there's a much easier way to communicate something as simple as water quality. If pHing to 6.5 cuts alkalinity in half, as I've read, and is the perfect pH for Cannabis in soil, is 1/2 of 275ppm an acceptable alkalinity? Who knows and it doesn't matter because that info is unconfirmed and most likely inaccurate.

The first entry in the glossary of my impending book:
Alkalinity - The measure of the amount of acid required to bring a solution to 4.29 pH.