Calcium Carbonate & CaCO3

King's Indican said:

Wow, internet is great. Read the whole thread especially @kratos015 posts hope he comes back. I am having similar issues to most of yours.
I used to grow with mineral nutes getting huge harvests then wanted to switch organics I like it but always get deficiencies around week 7-8
which looks like calcium deficiency, rust brown spots on leaves, upper stems turn purple, pistils turn brown in mid flowering and reduced yield. I still prefer the taste though. This happens to some plants while others grow perfect dense buds.
My mistakes: Overwatering sometimes (because of drip irrigation not by hand) and Overfeeding maybe.
I use 5G air pots filled with biobizz lightmix and worm humus (3:1) mixed with Biotabs products. Plants grow exceptional until flowering kicks in.
im using my tap water which comes at 0.43 EC. Let is sit for two days and put into Blumat reservoir and plant feed itself. I make compost tee and molasses feeds occasionaly.

Some people told me I must supply more calcium (gypsum) simply because what is in tap water and the nutrients is nowhere close to enough when growing under leds. This is the most advise I get. I couldn't believe it because the products I use all contain some ca and mg in it plus the soil and humus that I used combined with the ingredients of tap water.

Second option is soil ph gets too acidic when I overwater and locks out nutrients. I tend to believe this more because im growing them very humid the surface of the soil never gets dry.

And by reading this topic Im thinking maybe my soil ph is too high because of the caco3 presence in my tap water.
Im not a chemist or nowhere near that my head overwhelmed reading about many chemical compounds and how they react each other.
This last option looks more real to me now because I always get deficiencies later in the grow. ( salt buildup overtime) and it binds the calcium and plant looks like it needs it.

I have read many things about soft water hard water ppms etc.. It's all confusing different parts of the world using different ppm derivations.
It may not be the best but im putting my water analysis.

Should I brita my water then add some gypsum epsom?
or adding sulphur? sodium bicarbonate?
View attachment 5397690this chart is april 2024 and it doesn't show camg levels or caco3

View attachment 5397695this is the only one I could find showing what we need but it's from 2018

I never get any leaves yellowing between the veins described as mg deficiency. The last time I get it I was using Zerowater filter.
With this organic method I stopped buying zerowater filters and just used tap water which bring me issues I never encountered while growing with mineral nutes back in the day. I really love the way I grow now and the harvest quality just want to improve my yields. Providing some plant photos in 4x4 tent
View attachment 5397697at day 42 looking perfect
View attachment 5397698day 55 plant already slow flowering
View attachment 5397699you don't see but stems are purple, pistils withered.

I threw off my ph pen so I can't measure don't know if it's low or high but feeling what im struggling is the same things discussed in this topic.

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Hey there, I've been around. The land I got a few years back has been a huge project that has been keeping me busy. Way busy. May update when I find the time.

Anyway, onto your issue at hand. I highly doubt the issue is overwatering. At a glance, they don't look overwatered. Confirm the issue is in fact heavily calcified water prior to doing anything.

If you are on well water, or live in the desert/area with loads of rocks, excess CaCO3 is a likely culprit.

Not sure if my CaCO3 test is in this thread or not, but I'll post it once more anyway. Get yourself one of those liquid pH test kits, the color coded ones. Get yourself 3-4 cups, ideally clear.

Fill 1 with only your tap water.
Fill the other 2-3 cups with your soil, and soak it in your tap water. (More samples of soil in different places is best)

Let the water soak in the soil for 24-48 hours, then strain the water so you're only left with water in the cups. Now put your pH test drops into the strained water. If it is dark green (8.0pH or more) then your water is likely the issue.

In the meantime, put pH test drops in the cup with only water while you wait on the soil water to soak. It will likely test between 7.0-9.0 pH. Whatever your result is, ignore it. What you want to do is dump vinegar into that cup until the color shows as red (3.0-4.0 pH). Then, let it sit for 24+ hours. If in 24-48 hours the color is no longer red, but dark green, then your water likely has CaCO3 in it.

Liquid dolomite lime, essentially. Quite problematic, especially when many soil recipes call for (or include) lime in it already.

If you don't mind linking me to your water report, I'll give it a read sometime tonight. From the looks of it, the CaCO3 shows a 500 number. If that is for PPMs (likely is) then that is a buttload of CaCO3. My water in Arizona only had 400-420. Also shows the pH range between 6.5 and 9.5 area. Your faucets in the home have scaling in them? That scaling is CaCO3. In fact, you'll see that same scaling on the bottom of your pots. That is a for sure sign your water is hard and causing you issues.

The first thing I tried was making new soil without any lime, using my water to buffer the pH instead of lime. That worked great for the first few grows, until I had the same issue again. The big issue is for people that grow in pots. The water will be absorbed by the plants, or evaporate. The problem is that the CaCO3 will be left behind in your pot/soil.

With that in mind, this is also why the problem is rare when planted directly in ground. Water flows below the root zone. As a result, the CaCO3 left behind is below your root zone and thus, not impacting your grow. Outdoor plants in the ground never had this issue. Pots always did.

Get yourself some Langbeinite. May be too late to fix the issue this cycle, but if you're in a no-till, it should resolve itself by the next grow.

Langbeinite is a miracle for hard water, for 2 reasons. For one, the sulfur in it as actually sulfate (SO4), so it is readily available unlike elemental sulfur. The sulfate in Langbeinite will eventually break down the CaCO3 into individual pieces; Calcium, Carbon, and Oxygen. Individually, the plant can now process them and your pH is no longer out of whack.

2nd reason is the K and Mg in it. The 'excess' levels of K and Mg aren't so excessive when combined with hard water, because now your Ca, Mg, and K ratios are no longer out of whack.

tl;dr: Do the water test, and check for scaling on the bottom of your pots (assuming you use them multiple cycles). Once excess CaCO3 is confirmed, grab yourself some langbeinite asap.

Hope that helps. All the best.

kratos015 said:

The first thing I tried was making new soil without any lime, using my water to buffer the pH instead of lime. That worked great for the first few grows, until I had the same issue again. The big issue is for people that grow in pots. The water will be absorbed by the plants, or evaporate. The problem is that the CaCO3 will be left behind in your pot/soil.

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Whats up @kratos015 !! Thanks for dropping in. (thought you moved to Amsterdam! kidding) I'm finding that sodium plays a big part in the problems as well, that it coincides with the hard water we have in the desert areas. Have you had conversations or looked into sodium in the water source?

kratos015 said:

Langbeinite is a miracle for hard water, for 2 reasons. For one, the sulfur in it as actually sulfate (SO4), so it is readily available unlike elemental sulfur. The sulfate in Langbeinite will eventually break down the CaCO3 into individual pieces; Calcium, Carbon, and Oxygen. Individually, the plant can now process them and your pH is no longer out of whack.

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Langbeinite also has Magnesium and Potassium, I wonder if we could over do it with those two elements if the soil or dry amendments schedule already has those in the mix already. Upset the balance maybe?

kratos015 said:

2nd reason is the K and Mg in it. The 'excess' levels of K and Mg aren't so excessive when combined with hard water, because now your Ca, Mg, and K ratios are no longer out of whack.

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And there is the answer! ..lol, thanks!

kratos015 said:

Do the water test, and check for scaling on the bottom of your pots (assuming you use them multiple cycles). Once excess CaCO3 is confirmed, grab yourself some langbeinite asap.

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I know we've had conversations about langbeinite and I could look them up, but for the sake of this thread, and probably on here somewhere, ...what ratios per gallon do you reccomend? Tablespoon? And how often, once per cycle or every 3 weeks?
Appreciate ya Kratos..

Week4@inCharge said:

Whats up @kratos015 !! Thanks for dropping in. (thought you moved to Amsterdam! kidding) I'm finding that sodium plays a big part in the problems as well, that it coincides with the hard water we have in the desert areas. Have you had conversations or looked into sodium in the water source?

Langbeinite also has Magnesium and Potassium, I wonder if we could over do it with those two elements if the soil or dry amendments schedule already has those in the mix already. Upset the balance maybe?

And there is the answer! ..lol, thanks!

I know we've had conversations about langbeinite and I could look them up, but for the sake of this thread, and probably on here somewhere, ...what ratios per gallon do you reccomend? Tablespoon? And how often, once per cycle or every 3 weeks?
Appreciate ya Kratos..

Click to expand...

Alabama actually lol. Got a lot of the opposite problems out here that I did in Arizona. Out there, you had to work to get things to grow. Out here, gotta work to stop things from growing lol. And ironically enough, the blossom end rot on my tomatoes is a classic sign of Ca deficiency, something I obviously had zero issue with in Arizona.

Anyway, I've never heard anyone mention sodium in the past. Didn't have many grower friends, but even then, never mentioned.

Know nothing about it, sure someone more knowledgeable can chime in, but I do have a theory. Are you sure the issue is sodium itself, and not the result of some type of salt in which sodium in a part of?

Sodium, while not being a salt in itself, is a common ingredient in various natural salts that exist. Incidentally, chloride is often found in water like sodium. Knowing whether or not the sodium binds with chloride (or anything else) in the water upon the water evaporating is a thought I have, but is beyond my knowledge to say definitively that is the case.

It is worth noting that CaCO3 is technically, a salt.

As for the K, Mg, and Ca ratios. Ignoring them entirely for a minute, the biggest risk of 'overdose' would come from that massive K number. Very intimidating wanting to apply something 0-0-22 to an organic garden, when the highest NPK number is an 8 with most products.

The Langbeinite scientific article I linked to earlier in this thread many years back addresses the excess K in Langbeinite. According to their study plots, the field that was dressed with Langbenite actually had similar levels of K to the other fields with gypsum and elemental sulfur. Their thesis was that the extra K was made use of, either by the plants, soil web, Ca:K:Mg ratios, or a combination.

As for how I would dose it, I would apply it as a top dress according to the instructions on the bag. I top dressed according to the instructions every time.

Langbeinite is actually slow release due to it's structure and density.

Is it water soluble? Sure, but this will cause more issues and in the short term. The Mg, K, and S in Langbeinite were meant to be released slowly, over time, with each individual watering. The soil remains balanced this way.

Taking advantage of Langbeinite's water solubility, and applying it as a water solution as opposed to a top dress is going to release 100% of the langbeinite immediately, similar to a compost tea. Not what we want. We want slow, consistent, and over time.

I've not used Langbeinite since I lived in Arizona 1.5 years ago. But I always followed the bag's instructions. And I believe it said every 1-2 months.

If it is something you see yourself using often, Amazon has a 50lb bag for $80, as opposed to the Down to Earth product that is 5lb for $15-20.

Hope that helps, and all the best.

The type of calcium I prefer.

kratos015 said:

Alabama actually lol. Got a lot of the opposite problems out here that I did in Arizona. Out there, you had to work to get things to grow. Out here, gotta work to stop things from growing lol. And ironically enough, the blossom end rot on my tomatoes is a classic sign of Ca deficiency, something I obviously had zero issue with in Arizona.

Anyway, I've never heard anyone mention sodium in the past. Didn't have many grower friends, but even then, never mentioned.

Know nothing about it, sure someone more knowledgeable can chime in, but I do have a theory. Are you sure the issue is sodium itself, and not the result of some type of salt in which sodium in a part of?

Sodium, while not being a salt in itself, is a common ingredient in various natural salts that exist. Incidentally, chloride is often found in water like sodium. Knowing whether or not the sodium binds with chloride (or anything else) in the water upon the water evaporating is a thought I have, but is beyond my knowledge to say definitively that is the case.

It is worth noting that CaCO3 is technically, a salt.

As for the K, Mg, and Ca ratios. Ignoring them entirely for a minute, the biggest risk of 'overdose' would come from that massive K number. Very intimidating wanting to apply something 0-0-22 to an organic garden, when the highest NPK number is an 8 with most products.

The Langbeinite scientific article I linked to earlier in this thread many years back addresses the excess K in Langbeinite. According to their study plots, the field that was dressed with Langbenite actually had similar levels of K to the other fields with gypsum and elemental sulfur. Their thesis was that the extra K was made use of, either by the plants, soil web, Ca:K:Mg ratios, or a combination.

As for how I would dose it, I would apply it as a top dress according to the instructions on the bag. I top dressed according to the instructions every time.

Langbeinite is actually slow release due to it's structure and density.

Is it water soluble? Sure, but this will cause more issues and in the short term. The Mg, K, and S in Langbeinite were meant to be released slowly, over time, with each individual watering. The soil remains balanced this way.

Taking advantage of Langbeinite's water solubility, and applying it as a water solution as opposed to a top dress is going to release 100% of the langbeinite immediately, similar to a compost tea. Not what we want. We want slow, consistent, and over time.

I've not used Langbeinite since I lived in Arizona 1.5 years ago. But I always followed the bag's instructions. And I believe it said every 1-2 months.

If it is something you see yourself using often, Amazon has a 50lb bag for $80, as opposed to the Down to Earth product that is 5lb for $15-20.

Hope that helps, and all the best.

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Thanks @kratos015 always a pleasure to hear from you.

About to throw a monkey wrench into this whole discussion.. (maybe) or I'm an idiot for posting it here..lol.. no guts, no glory.. sigh

This was posted in April of 2012 (ICMAG) on one of their coco threads, so take it with a grain of salt. I'm reposting it here as there seems to be (some) cross reference to organic growers.



by delta9nxs



Hello, people!

“it is a fact that cal mag is necessary for optimum growth. Just ask any commercial or professional grower.”

"Well, yes, that's true, but I am a professional grower and I don't use any calcium or magnesium supplements because I don't have to. That's because I use a nutrient that already contains more than adequate amounts of each and I run ph at levels that allow for sufficient uptake. In the greenhouse hydro industry growing tomatoes with drip irrigation in perlite culture many operations use bulk nutrient preparations that are dry and come in two parts. One part contains everything but calcium nitrate, the other part is calcium nitrate. They keep them separate to prevent magnesium sulfate and calcium nitrate from interacting. Just as the gh flora series, techniflora nutes and many others do, liquid or dry. The one part flora nova gets away with everything in one bottle as it is a colloidal suspension that separates during storage, thus preventing the interaction. However, there are many nutrient packages that don't contain sufficient cal-mag. Pure blend pro is a classic example. You absolutely must use cal-mag with it to avoid disaster.

I am currently using maxibloom for flowering. It is a one part product that does not have any reactions until you put it into solution in water. It contains ample amounts of cal-mag.

The calcium/magnesium deficiency most folks run into eventually using hydro nutes is caused by ph being maintained at levels that don't allow for decent uptake. Not by the nutrients being low on either calcium or magnesium.

I know I run the risk here of opening up a whole can of worms on proper cannabis hydro ph, but here goes anyway.

Most of the ph charts you see are incorrect or misleading. Most would have you believe that if you don't run at a specific ph you are running the risk of lockout of one element or the other. Some depict uptake of elements at different ph points that don't even overlap with their recommendation for ideal ph, usually at around 5.8.

The truth is that there is no such thing as ideal ph and there are no finite points where lockouts occur. Every application is a compromise. However, the 5.8 recommendation is right in the middle of the range where you get the least calcium and magnesium uptake. You are still getting some, but usually not enough. You either have to get above 6.0-6.1 or below 5.5 to get adequate uptake of calcium or magnesium. I believe that above 5.5 phosphorus availability starts diminishing so I start my input solution at 5.2. As nutrients are used and evaporation/transpiration occur the ph will climb. The girls love it and show no symptoms of deficiency.

So, if you are using ro or distilled water and your nutrient shows calcium and magnesium on the label try running your ph between 5.1 and 5.4 for a while and see what happens. I think you will be pleasantly surprised.

If you are using ro water it is probable that you have very hard water from your tap and you decided to use ro water to solve the problem. If your tap water is over 200 ppm at the .5 conversion (milwaukee meters), you probably have too much calcium in your water. The calcium in your tap water plus the calcium in your nutrient solution can add up to an over abundance of calcium. An excess of calcium can cause a magnesium deficiency. You see the mag deficiency first and you think you need more magnesium so you add cal-mag thereby aggravating the situation. You can run into a similar scenario adding epsom salts (magnesium sulphate) to your solution. Too much of one nutrient can cause problems with uptake of another.

If your tap water is below around 150 ppm and doesn't contain more than 70 ppm calcium (only a water analysis can tell you this) try correcting ph to 5.2 for a while. With Ro water, if your nutes show Mg and Ca on the label, try 5.2 for a while.
Or you can blend ro water and tap water in proportions that get your tds below 100 ppm, then try 5.2 for a while.

My tap water is slightly over 200 ppm most of the time, so I blend tap 40%/ro 60% and end up with a reading of around 80 ppm before nutes are added. I chose this ratio because of the ph buffering capability inherent in the tap water mixed with ro at this ratio allows me to get away without using ph adjusters, either up or down. 2 gals tap plus 3 gals ro plus 2 level tablespoons maxibloom gives me 5.2 at around 950 ppm every time. I have visually perfect plants showing no signs excess or deficiency."