~350ppm Groundwater rich in natural calcium and magnesium. Can I use this and skip the Cal-Mag?

deimos phobos

Active Member
Hi all

I'm in a part of Canada where the townships water website even boasts about the natural Calcium and Magnesium richness of our hard water. The thing is, it's 315-345ppm out of the tap, when I've used my meters.

Here is a screenshot of the water report stats:



My questions are:

1. Should I dilute with RO or rainwater, and down to what PPM? Curious about both soil, and coco

2. If the water is usable, and with the stats shown above, would I be able to use the naturally occurring dissolved Ca and Mg and skip a synthetic additive?

I thought I had like 5 more questions but suddenly forgot them after a big dab so let's roll with this for now lol

THANK YOU !!
 

cobshopgrow

Well-Known Member
calcium and magnesium values looking not bad.
you can skip calmag for sure and wont need a fertilizer with a overly high value of calcium and magnesium.
all minerals listed there doesnt look to be bad in their ratios.
only concern, the listed minerals are less then 200ppm, whats the rest?
 

teddy bonkers

Well-Known Member
I use r/o water and a good complete nutrient. I never need to supplement cal/mag.
any good nutrient should have enough of those without needing to supplement.
I use r/o water so i can have as low ppm as possible to start.
 

Kassiopeija

Well-Known Member
Well problem with ppm readings are the different conversion factors, so plain EC is always best.

water looking good - a bit heavy on Mg (Ca:Mg = 2:1)

it should work fine on soil, you could add a half hand per sack (grossly estimated now...) of gypsum to the soil to get Ca + S higher (by x1.25 - x1.5) and stretch down the water using RO/rain to EC 0.4-0.5 (organic or Coco) or 0.2-0.4 (mineralic), but also depends a bit on whats already in the soil or how heavily precharged the coco is...

Ofc there are other ways to increase that, for Coco if you prefer bottled nutes theres Canna Mono Ca + Elementary Sulfur (heavily water dissolvable) which would allow you more control until its dialed in.

So basically the water is ok already but could be easily adapted/perfected to whatever method you grow by using RO & gypsum.
And since certain minerals (Mg, Ca, N, K) have the power to darken the leaf (when abundant) you could start low in water EC (0.2) and then go from there and increase once youll see your mature plants to "ask" for more (brightening up)

Salut :weed:
 

cobshopgrow

Well-Known Member
yea, its very medium specific.

only concern is, your water report isnt complete.
409 is the total mg/l, but the given elements in the analyse dont reach that.
there maybe something hidden.
a complete report would list that,, my waterworks do that f.e.
 

deimos phobos

Active Member
Hi guys I got an updated list direct from my township finally

Only thing that doesn't match up is the pH , mine comes out right around 7 from the tap! or 6.x

 

cobshopgrow

Well-Known Member
could it be that a few ppm are "hidden" as carbonates/alkalinity?

overall, good water.
slight high in chloride, but just slight
enough sulfate, as there is some in your fertilizer too.
magnesium and calcium are in harmless ratio, worth a try.

take some fertilizer for hard water and see if you can get the PH where you want it.
i assume youre in soil or coco.

for DWC the PH could give problems and the start EC is quite high for this.
 

Kassiopeija

Well-Known Member
Only thing that doesn't match up is the pH , mine comes out right around 7 from the tap! or 6.x
Did you calibrate/check the pH meter? Because this doesn't ring true... for example, where I live the accepted range of the pH of tapwater is 6.5-9.0. But usually, with all that chalk in your ater it should be much more alkaline, but you say it's actually slightly acidic...

tbh these values don't look that good to my eyes, as chloride shouldn't cross 30mg/l at all (optimally would be 1mg/l) but what's also missing is Sodium. Usually high amounts of Cl are caused by high levels of NaCl (household salt) so the Na would also be high. Both need to be low otherwise they will cause lockouts, because of ionic rivalry.

I remember you asked for help back at the other thread where your plants were quite yellow (although you did feed them) and this is exactly what high amounts of NaCl could cause.

I'd stretch that water with, at least, 50% RO water, or maybe even RO:Tap 2:1 plus small amounts of Calcinit & Epsom Salt (if you got a barrel for plant water somewhere...)

Aslo ask about Fe, Mn & Bor, some heavy metals can cause plant death if they cross a certain threshold....

No worries though - we'll get you through :blsmoke:

could it be that a few ppm are "hidden" as carbonates/alkalinity?
indeed, most likely CaCO3
 

deimos phobos

Active Member
Thanks so much for getting back to me -- you are AWESOME!

I stupidly forgot to mention I am running all of this water through one of these!!!


"HydroLife C-85"

I am fortunate to live in a farming region that feeds most of the Toronto area, and these farmers are all watering acreage with this same water. We are known for it being heavily chlorine/chloraminated sadly as there is a long pipeline involved, but somehow they are able to make it work without additional filtering. The C-85 to strip the chlorine & chloramine is a bonus the guys at Black Swallow are using, and when I went there in person, Andre was a big believer in the product and said thats literally ALL he used and we've got a similar water supply

So now I'm REALLY not sure to think

One thing is for sure, I thank you very much for your help so far!!

If you guys have donations setup somewhere for the site just let met know, I'm very grateful
 

2Hearts

Well-Known Member
Calmag and the calcium and magnesium in water are two different things and are not able to substitute each other.

Water with higher calcium levels will add a small amount to your soil lime buffer and not transfer into absorbable calcium in the region of 200ppm.

Just basic advice.
 

Kassiopeija

Well-Known Member
Thanks so much for getting back to me -- you are AWESOME!

I stupidly forgot to mention I am running all of this water through one of these!!!


"HydroLife C-85"

I am fortunate to live in a farming region that feeds most of the Toronto area, and these farmers are all watering acreage with this same water. We are known for it being heavily chlorine/chloraminated sadly as there is a long pipeline involved, but somehow they are able to make it work without additional filtering. The C-85 to strip the chlorine & chloramine is a bonus the guys at Black Swallow are using, and when I went there in person, Andre was a big believer in the product and said thats literally ALL he used and we've got a similar water supply

So now I'm REALLY not sure to think

One thing is for sure, I thank you very much for your help so far!!

If you guys have donations setup somewhere for the site just let met know, I'm very grateful
I use both, too (similar EU products - actually a 4 step RO setup).
Ask Andy how long he can use such a filter before it needs replacement. With hard water you may need to change it bi-monthly if overtly in use...

Cant compare outdoor to indoor. Outdoor theres rain (!) washing out salts plus much more divers biotop to break down chalk

Calmag and the calcium and magnesium in water are two different things and are not able to substitute each other.

Water with higher calcium levels will add a small amount to your soil lime buffer and not transfer into absorbable calcium in the region of 200ppm.

Just basic advice.
what happens if you pour citric acid over chalk?
just a basic question.
 

cobshopgrow

Well-Known Member
Hi guys I got an updated list direct from my township finally

Only thing that doesn't match up is the pH , mine comes out right around 7 from the tap! or 6.x

good eye, sodium was listed in his first report.
confusing.
the alkalinity could be mostly calcium carbonate, mostly is , isnt it?
while shouldnt be all the 255 mg/l ?
would filter the chloride also, but have to say it depends on how sensitive the plants are for chloride.
i have a similar value in the tap and it could grow, while i use 100% RO myself., having tons of sulfur and a bad ca/mg ratio.
most plants on planet can tolerate quite high chloride levels while they dont need it (btw, have one checked what Canna Mono Ca is made of in a technical datasheet?).
dont mix up chlorine and chloriDe.
chloride is "just" a salt.

if you have a RO and are unsure why not use it.
 

2Hearts

Well-Known Member
what happens if you pour citric acid over chalk?
just a basic question.

Over the residule calcium in tap water - you will make a tiny amount of chloride, still dosent represent 200ppm calmag like you keep on suggesting.

Use your question to source calmag, simply boil of ten litres of water and pour dry residue into your soil - now apparently you dont need any cal mag in your fertilizer.
 

Kassiopeija

Well-Known Member
Over the residule calcium in tap water - you will make a tiny amount of chloride, still dosent represent 200ppm calmag like you keep on suggesting.

Use your question to source calmag, simply boil of ten litres of water and pour dry residue into your soil - now apparently you dont need any cal mag in your fertilizer.
No you CANNOT create chloride by pouring C6H8O7 over CaCO3 - because, AS YOU CAN SEE - the ELEMENT "chlor" (Cl) isnt even contained in either of these compounds.

*Chemical* reactions will NEVER change the proton number of atoms - only radioactivity or supernovae can do this. (for starters)

So if you boil tapwater for some time the Ca will fall out and form chalk that is attached to the surface of your pot/cooker.
You never used clean vinegar or citric acid to dissolve it?

This is what a plants root exsudates are going to do with chalk that is in your water - just within a certain quantity...

but a grower could actually support & help a plant with this process:
(use on hard water only)
 

deimos phobos

Active Member
I can use RO but it's super wasteful and I was under the assumption that the naturally dissolved Ca and Mg in the water would be the same as adding a synthetic CalMag product to RO water..

Was trying to avoid needing RO water since the hardness already has a bunch of stuff in it

Didn't know they aren't the same thing :(
 

2Hearts

Well-Known Member
I was thinking of a hcl reaction.

The rest dosent make sense because of the huge variety of soil, potting soil is not really high in calcium a more clay loam topsoil might but still a lot is held in unusable forms. We would need more available forms for a peat soil as total availability is small and even the few ppms a plant can convert from tapwater are not going to sustitute a fertilizer or more calcium heavy soil.

The assumption i got from you was use 200ppm to sustitute ro water because tap has highly available calcium like calnitrogen or chloride and edta chelates which we find in calmag and ferts.





No you CANNOT create chloride by pouring C6H8O7 over CaCO3 - because, AS YOU CAN SEE - the ELEMENT "chlor" (Cl) isnt even contained in either of these compounds.

*Chemical* reactions will NEVER change the proton number of atoms - only radioactivity or supernovae can do this. (for starters)

So if you boil tapwater for some time the Ca will fall out and form chalk that is attached to the surface of your pot/cooker.
You never used clean vinegar or citric acid to dissolve it?

This is what a plants root exsudates are going to do with chalk that is in your water - just within a certain quantity...

but a grower could actually support & help a plant with this process:
(use on hard water only)
 
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