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Tap Calcium

f-e

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I have seen so many opinions regarding the usefulness of calcium in our drinking water supplies, It's confusing.

On one front, we have the idea that chelation will protect the calcium and magnesium carbonate ions from degradation, so they are available.

Another view is that P-acid will part out the calcium and magnesium, making calcium phosphate and magnesium phosphate that in tanked systems will fall out of solution.

Another view, that N-acid will part them out, leaving the same carbon dioxide and water as a byproduct. This time forming calcium and magnesium nitrate.

My basic sticking point here, is if my tap is 50 and my feed 50, do I ever have 100?


If I have 50 in my tap and wish to convert it from Calcium carbonate to Calcium Nitrate, how much N from acid might I need. 35ppm?

It troubles me.
 

gatts

Active member
Interesting topic f-e.

I'm using tap water filtered through 10mic and ceramic.

I was adding a lot of seaweed solution to one of my veg tents as a trial. It is high in calcium.

All the plants in that tent have suffered from Mag deficiency. The Skywalker Kush is the worst with a Skunk not too badly effected.

I put it down to too much calcium both from the tap water and added cal.

I swear by Epsom Salts now every other watering.

Does this help......https://manicbotanix.com/calculators/ppm-in-solution-calc.php
 

f-e

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Hello Gatts. I'm really leaning on Epsom to. It's one of the main denominators in how they get fed.
I couldn't open the link directly, but see it's a calculator. I read their page on P-acid and while very featured there was nothing relating to it's interactions.
The bulk of what I said before is from Harley Smith back in 2013. Some good info there about amino acid choices to chelate with https://www.easy-grow.co.uk/amino-acids-hard-water/

I do tend to use N-acid as I have known it helps with availability. I have not seen the big picture of how using P-acid sometimes has such an effect of my Ca though.

Just tapping away, each acid % is about a third elementally. I use that in my ppm sums. Calnit is ~ 66% calcium 34% nitrate. 2:1. When I add 12ppm of N using N-acid I could convert 24ppm of my taps 70ppm cal/mag from carbonate to nitrate. If my N-acid (I do like the abbreviation NCD in my notes) can fully dissociate. It seems PCD (p-acid) can only dissociate around 50% so adding 25ppm of P that way gives up maybe 12ppm P to interact with the cal/mag carbonates taking some out of solution. Not improving availability.

My chemistry is just what growing pushes me to know. So when I'm looking in new areas, their will be mistakes.

Edit: That reads terribly. I will clear it up more if I need to
 

troutman

Seed Whore
If I have 50 in my tap and wish to convert it from Calcium carbonate to Calcium Nitrate, how much N from acid might I need. 35ppm?

Ever mix baking soda and vinegar together?

If you mix nitric or phosphoric acid with calcium carbonate and magnesium carbonate in a bit of water in a jar it will fizz the same way
while giving off carbon dioxide. It you slowly add enough acid the fizzing will eventually stop. By then all the carbonates will have been
converted to nitrates creating basically homemade Cal/Mag. Test the pH before using though.

Watch this:

https://www.youtube.com/watch?v=_glnVLhYqxY
 

f-e

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Yes that's a good outline of what I'm talking about. The actual maths regarding the conversion potential in a tap water environment would be very useful. It's likely to be a simple ratio to get just a rough idea. Like maybe the 2:1 I came up with, based on a total implementation of the N added. Which is actually unlikely..

I know a total conversion would be a lot of acid in a hardwater area. The amount of NCD to get my solution down to 6.4pH was just that 11ish PPM. Using more is not on my mind, but knowing what that did would be nice.

Certainly some of out Tap's calcium can be used then. Maybe all of it if Amino acids are used, and in turn, some of them open up Ca pathways in the roots that improve transfer by a shockingly high margin.


On a personal note, my feeds fully chelated with black gunk, including humic acid. Perhaps I should first add my acid, to convert what I can. Then my feed to try and help chelate some more. Then the suppliments, as my feed should be as protected from them as it's ever getting.
 

f-e

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I put my usual dose of nitric in first, not last. It didn't do much to the pH. Next tank I put in 33% more. It's not done a lot either. It really should of. I have to presume something happening. My guess, the tap calcium usually gets protected by chelation before my acid goes in. Putting the acid in first, it's getting more chance to burn off the carbonites. Then to form the nitrate forms of cal&mag. Might be wishful thinking for all I know of chemistry, but something is different.
 

BillFarthing

Active member
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I always advocate using a fulvic acid to help chelate that calcium and put it to work for the plant. The other option is to use citric acid as pH down as a complexor. It creates a citrate/carbonate buffer that prevents the pH from drifting longer.

You had also mentioned 50 ppm carbonates, which is just about the perfect hardness for use in hydroponics.
 

Avenger

Well-known member
Veteran
the calcium ppm from a water test is certainly plant available, as it is a report of the calcium ions in the solution(water).

the alkalinity as reported as ppm CaCO3 is an equivalent representation of the acid neutralizing power of the water and not a measure of how much calcium carbonate is in the water. An alkalinity test measures the level of bicarbonates, carbonates, and hydroxides in water.

hardness is a combination of the calcium and magnesium in the water

https://ag.umass.edu/greenhouse-flo...t-practices-bmp-manual/water-quality-for-crop
 
G

Guest

American education system be like:


My water reads 400-600ppm
My hardness is reported as 16 gpg (274ppm)
Calcium listed as 90ppm
Magnesium as 25ppm

Calcium carbonate is 40% C. 90ppm 33% of 274. 90 + 25 = 41%

Solve for C

_-_-_--_-_-_-_-_-_-_
​​​​​​
All I know is when I started using LED, i found popular soil mixes very imbalanced, so I cut back a popular blend to 33% strength to find the weak link. The weak link was calcium.

The yields went from a few grams to a few ounces by doing nothing but switching from RO to my disgusting tap water with fulvic and citric added ( 20ml + 1/16th teaspoon). May sound like an exaggeration, but Leds in soil use calcium faster than the roots can grow into the medium to grab more. On top of that they don't drink so you're constantly Calcium deficient at the root tip between the sparce waterings. The availability of tap minerals and acidification is something I've been trying to figure out. I just had to look at a list of metabolites produced by soil microbes for it to sink in.. Calcium is old seashells. Seashells aren't water soluble, and therefore aren't bioavailable. So how the hell do microbes make oyster shell available? They produce acids that you can guy off the shelf. Now all these stinky microbe products really seem redundant next to the 5 gallon jug of Bioag.
 

f-e

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I have never found RO a good thing. It's just necessary sometimes. Generally there is good stuff in tap water. The link from Avenger indicates a minimum alkalinity of 37.5ppm should be expected from irrigation water to stop the soil going acidic. With 90ppm of calcium on tap, you should easily cover the needs of a calcium loving crop like canna. While some soil feeds don't even think to give you any.
I'm doing an RO run to find an illusive problem. I really hope that RO isn't the fix I need. Mixed opinions mean I have to do the testing though. My last full RO grow looked alright, but half the weight was missing. I'm not happy to be doing it again.
 

Ca++

Well-known member
I always advocate using a fulvic acid to help chelate that calcium and put it to work for the plant.

I think this holds a lot of weight. I have heard stories of precipitation like falling diamonds, when P went into hard tanks. Hurley talks of it, and how hardness would form around the water level in his tank. Then he started using yukka. A wetting agent that can be chelate agent. The hardness stayed in the water, to reach the plants. Though it's just an observation. This could be just the wetting agent allowing the calcium-phosphate to stay in solution. What I'm interested in, is if I can first add nitric, to convert some calcium-carbonate. Then a chelating agent, to reduce the interaction between my hard water and P inputs.
I know my chelated one part, has P and Ca in the same bottle. It's fully chelated, and contains the soil acids, which I'm presuming are doing some of this work. I tried an A&B feed recently, with double the P, and got P deficiency. I have to wonder if chelation would of cured an unseen problem, where P (and Ca) were actually lost.

Maybe it's all a do about nothing, and feeds are formulated to expect ec0.4 tap water. However, If I can stop calcium phosphate being created, that's probably Calcium and Phosphate I can more readily use.

That's todays 11pm coffee break over.
 

Nannymouse

Well-known member
Our water company's site shows a photo of them taking calcium and magnesium out of the water. I don't know how much might be left in, after that process. The water reports do not list those.

I'm wondering how you guys know which particles are in your tap water? TDS meters don't differentiate between the particles, do they? We get a lot of water from the 'big muddy', so who knows what particles are in there.
 

xtsho

Well-known member
Our water company's site shows a photo of them taking calcium and magnesium out of the water. I don't know how much might be left in, after that process. The water reports do not list those.

I'm wondering how you guys know which particles are in your tap water? TDS meters don't differentiate between the particles, do they? We get a lot of water from the 'big muddy', so who knows what particles are in there.

Doesn't your water company post test results of the water entering the distribution system? The water Bureau here posts water quality data showing a detailed breakdown of what's in the water and how much.

Sometimes it's hard to find that information. Often googling "water quality report [city] [state]" leads to that data.
 

Nannymouse

Well-known member
We get one mailed to us and it is on the website, they just don't report how much calcium and magnesium there is. Maybe it is zero. I could call, i suppose.
 

Nannymouse

Well-known member
I double checked their site, they only have a contaminant report, nothing exciting that i can see. They list an alkalinity, which they say they 'remove' to acceptable standards. And then they say that they mix it with the nearest city water. Well waters are involved. So, it's still sort of an open question. I'll have to find where FL listed his water results, i think that he used some home test kit.
 

Ca++

Well-known member
I get a runoff report for £30. They are not looking at it as drinking water, which costs a lot more. It's just the stuff in my feed.
 

Ca++

Well-known member
Just had a fail. I put some seaweed in my tank first, to try to chelate the calcium. I have no idea if it's a viable idea, so was having a crack at it. Made my tank up. Left it 3 days to just sit about. What I left was black water, what I found was like a milkshake someone tried to flavour with orange cordial. Or the out of dare milk in my fridge, that's started to separate. Like millimeter sized blobs of the black seaweed, all separated by a 1mm film of clear water. Clearly separate suspended solids, though not solid in any way. A stir did nothing.
The interesting thing for me, was the pH. I had left it around 5.5 and my tap is in the high 7s. This water was in the 8s. The seaweed thing I use has a high pH, I use it as up. It's a K source iirc.
I corrected the pH, but having used as much acid as I did the first time, I chucked it away. However, I'm still using a second tank, I have not metered again. The plants are doing well enough that I'm not chucking it away. My plants like this stuff, and though I usually add it last, I am aware of this curdling and some pH shift. Just not into the 8s.
It's seriously countered the acidity over time, yet doesn't seem to want it corrected again.
It's difficult.

My dosing might be high, as the bottle is talking a fair few ml per Liter. It's pretty dirty stuff at full rate. You don't want to put your hand in the tank, or it will need washing.
 

Nannymouse

Well-known member
Sounds like something that i would attempt, ha. I know, not funny.

But i really loved the 'out of dare', i think that i shall hitherto consider that date as the 'dare' day. Love it.
 

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