Water Cal/Mag ratio

[Caly]

I did my water test with GA a few weeks ago, I’ve got hard water at 0.5ec and have been given advise to add Epsom salts with their hard water feed .

[zen-ken]

13 hours ago, Oldbear said:

Depends, if you don't know your starting point what ratio do you add? Blindly banging in calmag is often a greater cause of trouble than cure. 

 

[ratdog]

according to the info on the tropic mix bags the ratio for cal to mag is 2:1

 

 

[zen-ken]

I would suggest most Cal/mag diagnosed issues are more to do with over use of potassium than the need for Cal/mag. (ref mulders chart)

The perfect ratio is somewhere between 3:1 - 2:1 depending on method. (various sources)

 

But this doesn't tell us the story...... 2:1 ??? how much do you add then ? what does it mean ? 500PPM Ca to 250PPM Mg and we all good then ?

Most products don't even break the elements down for you 

 

It would be a better shout to understand the ppm the Cal/mag needs to make up in the final solution in relation to the NPK levels (in particular K)

The reason for a water test surely is to try to shape your feed to accommodate levels required.

 

Or just ask for 'more cow bell'  

[Caly]

4 hours ago, Oldbear said:

Just out of curiosity, what was you calcium and magnesium levels? 

Results and comments for your water test are below. Values in parts per million (ppm) except pH.

 

Calcium     88

Magnesium  1

Sulphate      7

Alkalinity     280

pH              7.60

[Shumroom]

@Oldbear....... 

 

Edited November 12, 2021 by Shumroom
Oldbear got there first

[Caly]

48 minutes ago, Oldbear said:

OK, you'll need 28ppm mg to set at 3:1. Epsom salts are harder to measure for accuracy than mono mg. You'll only need 0.4ml per litre of mono mg to water to correct however so it's not a major correction. 

I am curious as to how a company that does made to suit feeds winds up asking you to correct it

 

 

They sent me all the correction measurements I need per litre.

[ratdog]

Just now, Caly said:

They sent me all the correction measurements I need per litre.

 

 

good guys there, they only do the hard and soft unless you want tailored nutes.

 

i still need to watch my ph with my shitty soft water

 

when i use up this lot i'm going to give coco a go, i'm not going to be organic anymore, so what's the point of soil?

[Caly]

Just now, ratdog said:

good guys there, they only do the hard and soft unless you want tailored nutes

They told me the correction is minimal and I would save myself money just by adding some Epsom salts to my water first.

[ratdog]

Just now, Caly said:

They told me the correction is minimal and I would save myself money just by adding some Epsom salts to my water first.

 

 

yeah, they like to help, i think someone else in this thread got help from them without buying their nutes

[Wacky Wardrobe]

Just now, Caly said:

They told me the correction is minimal

Did they say how much Epsom's to correct yours?

I add a little bit of Epsom's to mine to correct the base water ratio before adding calmag to raise the overall level as I'm in coco at the mo and it's moderately soft here.

I'd be interested to see what they recommended for yours to compare.

[dan6]

Hi.

I was advised by Growers Ark to add 1/2 a gram of Epsom Salts per 2 litres of water..... my analysis was.....

Calcium         133.2

Magnesium    4

Sulphate        54

Alkalinity        329

pH                7.20

Hope thats helpful to someone

Dan

[Caly]

1 hour ago, Wacky Wardrobe said:

Did they say how much Epsom's to correct yours?

They did, I’ll link it later 

[Caly]

4 hours ago, Wacky Wardrobe said:

Did they say how much Epsom's to correct yours?

Yes I would recommend using  our hard water food and the addition of Magnesium Sulphate (Epsom salts)  at the rate below to ensure the Ca:Mg ratio is in the best range.

If using at 4ml/liter (recommended rate)

 Add  2 grams of Epsom salts to 10 liters of water dissolve then add food and adjust pH to 6.4 for coco.

If using at 3ml/liter add 1.2 grams 

If using at 5ml/liter add 1.5 grams yes that's correct (adding more Mg from food so counterintuitive result from calculation)

[Caly]

1 hour ago, Oldbear said:

I'm still a little confused as to why they don't mix a feed with correct ratios for your water? 

They said it was just a minor adjustment and just by adding the salts it would save me money (and them effort I guess)  to make up a custom feed