Water Cal/Mag ratio

[EarLobe]

6 hours ago, mysticriver said:

The tap PPM is ~680 - 0.6-0.7 ec.

Get a filter if its that high mate. I wouldn't even drink that...

 

E2A Google Paste:According to the EPA secondary drinking water regulations, 500 ppm is the recommended maximum amount of TDS for your drinking water. Any measurement higher than 1000 ppm is an unsafe level of TDS. If the level exceeds 2000 ppm, then a filtration system may be unable to properly filter TDS.

Edited October 21, 2021 by EarLobe

[Periodic]

I rang them  (Severn Trent) up and asked the Ca/mg in my area, (Sth..Leics.)

the technical people rang back and it is  5/3 Calcium to magnesium,

I'm not sure what to do with the information but they will happily talk to the public.

 

[zen-ken]

7 minutes ago, Periodic said:

I rang them  (Severn Trent) up and asked the Ca/mg in my area, (Sth..Leics.)

the technical people rang back and it is  5/3 Calcium to magnesium,

I'm not sure what to do with the information but they will happily talk to the public.

 

You could increase cal to mag ratio

 

https://www.cannabisbusinesstimes.com/article/balancing-the-nutrient-equation-cannabis-cultivation/

 

[Gaijin]

Morning gents  

 

Interesting stuff. Part of me wants to dig deeply into this  ...... and part of me wonders if I really need to get too far into the details when it'll be my very first grow, in compost. Should I back away from this thread slowly?   I have gone as far as checking the SE Water website, but I'm not sure what to make of the following. Other than, it's hard and have 20.11 English Degrees, which sounds wonderful  Should I be concerned? 

 

2. Your water hardness

287 mg/l CaCO₃

20.11 English degrees or degrees clark
28.73 French degrees
16.09 German degrees
2.87 mmol/l
16.09 Grains per US gallon
20.11 Grains per British Gallon

This means your water is classified as hard

[Newcouch]

15 hours ago, EarLobe said:

This is what you'll get guys. Worth every penny. Keep checking your water as mine can vary sometimes. Changed the pipes a few years ago and lost a few ppm somewhere....

 

we have tested your water, results and comments below. Values are in parts per million (ppm) except pH.

 

Calcium          85           

Magnesium     4              

Sulphate         49

Alkalinity         219

pH                   7.4            

This is a moderately hard water with medium/high levels of Calcium and Alkalinity and fairly low Magnesium.

This water is just on the edge of having a CA:Mg ratio of ok when using our hard water coco food and just below if using our hard water Hydro food. It's in the good range for soil.

We would recommend using our hard water food with this water (some pH adjustment will probably be required after mixing). For both the Hydro and Coco food we would recommend adding 1g of Epsom salts to every 10 liters of water used along with the food to bring the Mg level up to a better range.

Hope this was helpful any questions get back to us.

Kind regards and stay well

Martin for Growers Ark Ltd 

 

This is not a million miles from mine.

 

Alkalinity as CaCO3: 232 mg/l
Carbonate as CO3: 139.2 mg/l

Calcium: ~98 mg/l
Magnesium: 2.8 mg/l
Sodium: 8.2 mg/l
Sulphate: 10.4 mg/l
Chloride: 21.6 mg/l

PH: 8.23

 

I am a little surprised by what growers ark say.  But then they seem to say two things. It seems the general acceptance of best calmag ratio on this forum is 3:1.  Both of us have calmag levels well above that; 20 even 30 to 1. Their hard water nutes must do more adjusting than expected, but not enough. I am a bit wary of the nute blend doing so much for me - there are many different types of hard water - just what are they assuming?? How do they know the buffering capacity of your water? They must be guessing an average. Obviously, when you get the water done by them, then this resolves itself.

 

Another post said;

Fwiw, cheap as chips epsom at 0.1g per litre will give you +10ppm of Mg

 

So my calculation for my water was;

 

So i have 98 ml/l = 98 ppm Ca and 2.8 ppm Mg and i need a ratio  of 2.5;1 to 3:1  or about 27ppm Mg

 

So just 2.6g in 10L of epsom salts.

 

So growers ark are giving you 85/14 ratio = 6:1

 

In the end, i just chucked in a hearty pinch of epsoms at about a week 6 watering (i had pre fertilised soil - big mistake).

 

The takeaway from this is that Mg ratios arent as exact as thought. medium hard water often has sufficient calcium but needs mg adjusting which is ridiculously simple using epsom salts.

You do need to watch ec levels when adding epsom;  My hefty pinch added 40ppm in 5L whereas 5mg of chempack only gives 250ppm.

 

[zen-ken]

@Newcouch

 

I think you would find this interesting https://digitalcommons.murraystate.edu/jahr/vol2/iss2/1/

 

The results are suggesting a PPM of over 50 

 

[mysticriver]

17 hours ago, EarLobe said:

Get a filter if its that high mate. I wouldn't even drink that...

 

E2A Google Paste:According to the EPA secondary drinking water regulations, 500 ppm is the recommended maximum amount of TDS for your drinking water. Any measurement higher than 1000 ppm is an unsafe level of TDS. If the level exceeds 2000 ppm, then a filtration system may be unable to properly filter TDS.

I have a 5 stage r/o filter that also filters without the r/o membrane - I drink that

 

 

mysticriver 

[mysticriver]

16 hours ago, Periodic said:

I rang them  (Severn Trent) up and asked the Ca/mg in my area, (Sth..Leics.)

the technical people rang back and it is  5/3 Calcium to magnesium,

I'm not sure what to do with the information but they will happily talk to the public.

 

Thanks for that bro

here is the Severn Trent Water quality report

 

As you can see its got nothing under calcium and magnesium, so thank to @Periodic for phoning them.

 

 

mysticriver 

[mysticriver]

15 hours ago, zen-ken said:

You could increase cal to mag ratio

 

https://www.cannabisbusinesstimes.com/article/balancing-the-nutrient-equation-cannabis-cultivation/

 

Whats the ideal cal/mag ratio? is it 3:1?

 

 

mysticriver 

[Wacky Wardrobe]

Hey @mysticriver.

I just had a look at this.

It's weird that they don't specify cal and mag amounts but I understand you should be able to deduce from the info you have.

Apparently the clark hardness number is telling you how much calcium it contains. You just need to convert to ec or ppm. (Or should that be mg/litre?)

The info you got about the ratio between cal and mag ratio (5/3) allows you with the calcium figure to deduce how much magnesium.

I'm crap at maths so I won't try and do it for you.

Hope this helps.

Edited October 22, 2021 by Wacky Wardrobe
mg/l

[zen-ken]

Should be another page to that water report....'Indicator perimeters' and 'other perimeters not covered by the regulations' 

Edited October 22, 2021 by zen-ken

[Wacky Wardrobe]

@mysticriver Just above where your screenshot starts they show hardness in a number of scales.

Here's a conversion chart.

[EarLobe]

Very interesting information from your water supplier. I would still approach with caution as you don't know what you water picks up or loses on the way to you. Old or New piping, the ground and even the type of plumbing in your house can affect what your water supplier sees and what you get out of your tap!

 

All the best with this. I had a nightmare for months with my water. FWIW Mono Magnesium I found a lot easier to administer and control then epsom salts. I use so little I buy between expiry dates rather then in running out!

[mysticriver]

21 hours ago, Wacky Wardrobe said:

@mysticriver Just above where your screenshot starts they show hardness in a number of scales.

Here's a conversion chart.

 

OK so here is the bit you mention 

 

And here is a bit of blurb about hardness...

 

At the top they say hardness is calcium and magnesium present in the tap water

Then at the bottom they clarify that the water hardness figure of PPM [ml/l] is for calcium carbonate (only?)

I understand then that there is ~20ml/l. Of calcium. In my tap watter.           WRONG

What can I do with this information? Do I have to add magnesium @ ~7ml/l to bring the tap water to the ideal ratio?

Still a bit fuzzy (if u pardon the pun)

 

 

mysticriver 

 

Edited October 23, 2021 by mysticriver
WRONG

[mysticriver]

I know ive got the 20 figure wrong and its something to do with the conversion scale but its out of my maths capabilities.

im gutted cos ive been doin so well with maths recently...

 

 

mysticriver