Measuring Calcium & Magnesium Levels - Coco Noir

[Cmoon]

Hi from the UK.

I'm a newbie starting out in the wonderful endevour of growing my own weed. As you are probably aware this is still illegal in the UK with draconian punishments (Prison) for those who try it. Do I give a F**K? Not when I read of the good it could possibly do me.

So I did lots of reading got some feminised seeds (autoflowering), 2 grow tents just small ones, both 2' x 2' x 6' high and succesfully got eight palnts growing nicely. They are now about a foot high after 5 weeks but they look dry and are starting to yellow mainly on the big lower leaves.

I got them growing with root riot (which was great) then transferred them to small pots using coco noir and nutrients and they all seemed to grow well. I have a 300watt metal haide and a 300watt LED In the tent. I keep the temp between 72C and 80C.

What I have overlooked is Calcium and Magnesium, but I'm not paying the price they ask for Calimagic, that's just plain ridiculous. Now, I have keept marine fish and a coral reef alive in my live roon for many, many years now and I am familure with dosing with Caclcium & Magnesium to very fine tollerence levels. And it is very cheap to do so. My question here is what type of Calcium and what levels measured in PPM (parts per million) Should I make my water up with? I can then test the water with an aquarists test kit.......Simple.

This was really just to say hi but I wanted to ask this specific question as my plants are now not looking quite right and I'm convinced it's the Calc/Mag.

Any help will do and that's for letting me in to your club........

Cheers

Simon.

 

[Scientific]

I admire your DIY spirit, but wonder after all is said and done if just buying a bottle wouldn't be easier.

CALiMAGic is:
1% nitrate nitrogen
5% calcium
1.5% water soluble magnesium
0.1% chelated iron

Derived from calcium carbonate, calcium nitrate, magnesium nitrate, and iron DPTA.

Recommended dose is 1 ml/liter.

I'll leave the required calculations to you.

 

[Cmoon]

Many thanks Scientific.

Have spent most of today trying to find a supplier of CaliMag in the UK...... Not a chance! We are way behind you over here so it is more or less learn and do it your own way, so hear I go.......

I am now the proud owner of a pot of

1: G&G Vitamins Magnesium Carbonate Powder (100grams) Calcium Carbonate Powder, Pharmaceutical grade, (1lb)

2: Calcium Carbonate Powder, Pharmaceutical grade, (3.5 oz)

3: A giant bucket of epsom salt 100% Natural | FCC Food Grade | Magnesium Sulphate! (10KG BUCKET) For you and I who still speak in English and not EU.........that's about 25lbs in weight!.......Might have over done it just a tad with the epsom salts but it was all I could find. At least I might have some left over when I get out of jail!

4: Pint of pH down.

5: I also got a bottle of Everclear for future use that cost only $118 but I'm ok with that, it's probably cheaper over there but I can't get my daughter to post it.

Now if only I new how to mix my base feed (with Calc, Mag, & pH at 5.8) before I add nutes & stuff, I will be fine. By the way I don't smoke so am going down the tincture route or heat press. Thanks again for your help.

PS. should I be posting this in a different thread?

 

[Scientific]

In future you might just want to get a sack of garden powdered dolomite lime, which is Ca and Mg carbonates, but cheaper.

Both calcium and magnesium carbonate will dissolve in acid medium and in fact raise pH as they neutralize acid. (Antacid tablets like Tums are made of calcium carbonate.) So just working them into acidic soil will do the job.

Alternatively (and I think this is the route that I'd go down) you add x grams of each to water and then add pH Down until both dissolve and you reach the desired ph (in the mid 5s for soil is best if I remember correctly). It will take some time for the carbonates to dissolve in the acid of the pH down, so wait until all the powder is dissolved, which may take a while, though my memory is that dolomite went into solution very quickly in an only slightly acidic planted fish tank.

Cannabis growers do seem to like Epsom salts. All those sulfates that go along for the ride always made me uncomfortable. Moi, I'd stick with the carbonates and add the Epsom salts in your bath water. Add add some Everclear to some tap water and have a nice cocktail! (Serously, I'm a big tincture guy, so I get the EtOH thing...)

PS: I think this FAQ thread is fine for this discussion, though there may be (should be?) a fertilizer thread around here somewhere...

 

[Scientific]

One more thought... I remember that some beers/ales in the England benefited from calcium present naturally in the water. Do you know the PPM readings of the water you are giving your plants? (If not, you should. Buy a meter. They're cheap and tell you a lot.) If the water in your neck of the UK is over 50 PPM, you may want to check with your water utility (most have websites here) to try to find out what's in the water (how "hard" it is, usually specified in grains). You may not even need supplements for minerals that are there naturally...

 

[Cmoon]

Hi and thanks for the help, I really appreciate it.

So the Calc & Mag act as buffers for the pH down to keep it stable, is that right? My problem is I don't know how much the ratio between Calcium and Magnesium powder to ad to say 100 liters of tap water (which is pH7.8 as it comes out the tap). I have a TDS meter & I do also have calcium test kits somewhere, I'll have to dig them out.

I'm so used to dosing sea water which is around pH 8.5 with calcium which has first to be disolved in Co2 and drip fed into the aquarium, so I'm kinda thinking upside down if you see what I mean?

Cheers
Simon
Oh and I have stacks of beer!!

 

[Scientific]

> So the Calc & Mag act as buffers for the pH down to keep it stable, is that right?
Calcium and magnesium are in the same column in the periodic table (row #2). As such they're very similar--they're light metals that form ions with a +2 charge.
Carbonate--CO3--has a -2 charge, so it links nicely with Ca and Mg to make CaCO3 (a.k.a chalk) or MgCO3.
When you put CaCO3 or MgCO3 in water, they don't dissolve, but if you acidify the water (with the phosphoric acid in pH Down), the Ca and Mg go into solution as a CO2 bubbles off into the atmosphere.
That mixture is resistant to change in pH, which is the definition of a buffer.

But as interesting as all that may or may not be, I think this issue might be moot for you. If your water is pH 7.8 out of the tap, and given your UK locale, I think there is a very good chance that your water already has plenty of Ca and Mg in it already. Dig out your TDS meter and calcium test kit and see what they say, and check with your water utility or a knowledgeable gardener/gardening supplier/agricultural service to see what's already in your water.

The water where I live comes off the ocean, falls onto basaltic and granitic rock, and returns to the sea again as pure as it fell from the sky. We have so little mineral content in our water that the utility has to actually add some to help protect the pipes. Consequently, I have to add lots of CALiMAGic to my grow. But I'm guessing you prolly don't gotta, so all this may just be academic.

 

[Cmoon]

Yup, Gotcha! So I was going to start off with RO water to avoid the effects of the crap they put in our tap water, like this quote from the independent group of specialists from new scientist........

"Many prominent scientists are alarmed by the content of some drinking water and actively seek to change the processes involved. The practice of making water safe to drink actually involves adding large amounts of extremely poisonous chemicals to it. Key scientists are now providing evidence that long-term ingestion of small amounts of chemicals like these could be the cause of some major health problems.

Here is a list of just a few of the chemicals routinely added to our water supply:

Liquified chlorine
Fluorosilicic acid
Aluminium sulphate
Calcium hydroxide
Sodium silicofluoride

Even if the water leaves the source in a relatively clean state, don't forget that your water travels through pipes, which may have been underground since Victorian times. It is almost impossible for the water not to become contaminated by something undesirable.

Contaminants in Tap Water

Tap water is treated with a large number of chemicals in order to kill bacteria and other microorganisms. In addition, it may contain other undesirable contaminants like toxic metal salts, hormones and pesticides, or it may become contaminated by chemicals or microbes within pipes (e.g. lead, bacteria, protozoa).


Typical Tap Water Content:

Chlorine
Fluorine compounds
Trihalomethanes (THMs)
Salts of:
arsenic
radium
aluminium
copper
lead
mercury
cadmium
barium
Hormones
Nitrates
Pesticides"

So if you drink our water you may glow in the dark but you wont have very good teeth!
That was my reasoning for using RO water but I think I'm just gonna go with the tap water first & later maybe mix up my own with RO.
So, all I have to do is add pH down to about 5.6 then add Calc + Mag to a measureable amount because if there's too much C + M the roots won't be able to take it up right, then check the pH is correct and there we are, good base water?

Seriously, many Kudos for your helping me through this, I'll get there in the end.

Cheers
Simon

 

[Scientific]

Water in first world countries is generally safe to drink. I wouldn't worry about water in the UK unless I was drinking well water in an agricultural district or living in an area known to have problems with ancient pipes or whatever.

That list of "chemicals routinely added to our water supply" strikes me as fear mongering. For example, chlorine is a poison gas, yes, but in small doses it does far more good than harm by killing pathogens that may find their way into a pipe. CaOH is caustic in concentrated from by harmless at the levels you'll find it in your glass; it could even be considered a nutrient. And fluoride compounds--well, the crazies have been going off about Fl in drinking water for half a century and meanwhile our teeth are all stronger.

As for the rogue's gallery of poisons, if your water has any of those, you are in trouble, but it doesn't. Go to the website of your water utility and look. Assay methods are so incredibly good now that scientists can detect chemicals in vanishingly small amounts, but there's not enough there ever to worry about in developed countries (unless you live is a sh*thole town like, Flint, MI, in which case you have more problems than just water...)

> So, all I have to do is add pH down to about 5.6 then add Calc + Mag to a measureable amount because if there's too much C + M the roots won't be able to take it up right, then check the pH is correct and there we are, good base water?

No. You'd add the desired amounts to your water and then acidify to the desired pH. That's going to take some time and fussing as the powdered carbonates are going to have to dissolve. And I'm sure that you really can add to much Ca and Mg. Plants don't just shut down absorption, at least not that I've ever heard of.

You SURE you can't get a bottle of CALiMAGic? Or maybe just add dolomite lime to your soil. Your agricultural extension service or local gardeners can probably tell you how. Or get your chemistry books out of the boxes in the garage and do the calculations. No one said DIY was gonna be easy!

 

[Weezze]

So I did lots of reading got some feminised seeds (autoflowering), 2 grow tents just small ones, both 2' x 2' x 6' high and succesfully got eight palnts growing nicely. They are now about a foot high after 5 weeks but they look dry and are starting to yellow mainly on the big lower leaves.

You have 4 plants in each 2x2 tents? That must be tight! What is the size of your pots?
Do you have pictures?

 

[Cmoon]

Hi Weezze,
Cheers for the reply. I actually have 8 plants in one tent! (2'x2'x6') and yes it is getting cramped. I got the second tent to move them to the flowering stage when they were ready and because they were not all the same strain or even supplier I figured they would not all bloom at the same time.

I have done a few pics with all eight in the one tent (as they are now) but I do think the two at front left and front right are starting to bud & I think it might be time to take them out and put them on a 12/12 cycle.

Here is the grow tent. It just has mylar as a reflector because I could not dissipate the heat with the full tent over it. There is no roof so the hot air from the halide is blown up and out the top.

 

[Scientific]

Supplementing with Calcium and Magnesium Carbonate

Updated. See post below

 

[Scientific]

Supplementing with Calcium and Magnesium Carbonate

It's a lazy Sunday afternoon, so I skipped doing the crossword and did the calculations to use your CaCO3 and MgCO3 to supplement your grow.

To make a 100X CaCO3 + MgCO3 solution, add 10 grams calcium carbonate and 4 grams magnesium carbonate to a liter of water, then add pH Down until the powder goes into solution.

Note:
I expect that the carbonates will be dissolved as soon as the solution in acidic (< pH 7.0), though it might take some time. Mix, wait, measure, repeat until pH and PPM readings are stable.

To use the 100x solution, add 1 ml of it to each liter of water for the plants.

The water to which you're adding the 100X should be acidic or the carbonates may crash out of solution (the symptom of which would probably be the added 100X would look cloudy as it was added to the plant water.) CaCO3 (which is just chalk, right?) and MgCO3 will not stay in solution in neutral or alkaline water. Adjust the pH of water you're going to add to the plants to the correct range again before adding to the plants.

If anyone uses this concoction, please message me to let me know if iit works for you. (Maybe try in on the petunias first? And check later in this thread for any updates or corrections.)

As an alternative, you could just add dolomite lime (which is about half and half Ca and Mg) to acid soil.

The calculations. Check my arithmetic!

General Hydroponics CALiMAGic
Directions: (Typical dose recommended by GH) Add 2.5 ml to each 3.79 liters of water.
946 ml per bottle
Bottle weights 1.14 kg

Analysis:
5% Ca
1.5%Mg

Ca
5% of 1140 gram bottle=57.0 grams Ca per bottle
2.5 ml dose/946 ml per bottle= Use 0.0026 bottle per 3.79 liters H20
.0026 bottle *57 g Ca per bottle=0.1482 grams Ca per 3.79 liters H2O
.1482 g Ca /3.79 liters =0.0391 g Ca/liter H2O

CaCO3
CaCO3 weighs 100 grams per mole
Ca weighs 40 grams per mole
CaCO3 is 40/100 = 40% calcium

Dosing Ca:
.0391 gram calcium per liter H20 * 100 g CaCO3/40 g Ca gives 0.09775 gram CaCO3/liter H2O
To make 100X strength solution, add .09775*100=9.775 grams CaCO3 to 1 liter H2O

Mg
1.5% of an 1140 gram bottle=17.1 grams Mg per bottle
2.5 ml dose/946 ml per bottle=0.0026 bottle per 3.79 liters H2O
.0026 bottle *17.1 g Mg per bottle =0.0445 grams Mg per 3.79 liters H2O
.0445 g Mg/3.79 liter H20=0.0117 g Mg/liter H2O

MgCO3
MgCO3 weighs 84 grams per mole
Mg weighs 24 grams per mole
MgCO3 is 24/84=0.2857 or 29% magnesium

Dosing Mg:
.0117 g Mg/liter H2O * 84 g MgCO3/24 g Mg=0.04095 grams MgCO3 per liter H2O
To make 100X strength solution, add .04095*100=4.095 grams MgCO3 to 1 liter H2O

 

[Scientific]

Re: Supplementing with Calcium and Magnesium Carbonate

It's a lazy Sunday afternoon, so I skipped doing the crossword and did the calculations to use your CaCO3 and MgCO3 to supplement your grow.

To make a 100X CaCO3 + MgCO3 solution, add 10 grams calcium carbonate and 4 grams magnesium carbonate to a liter of water, then add pH Down until the powder goes into solution.

Note:
I expect that the carbonates will be dissolved as soon as the solution in acidic (< pH 7.0), though it might take some time. Mix, wait, measure, repeat until pH and PPM readings are stable.

To use the 100x solution, add 1 ml of it to each liter of water for the plants.

The water to which you're adding the 100X should be acidic or the carbonates may crash out of solution (the symptom of which would probably be the added 100X would look cloudy as it was added to the plant water.) CaCO3 (which is just chalk, right?) and MgCO3 will not stay in solution in neutral or alkaline water. Adjust the pH of water you're going to add to the plants to the correct range again before adding to the plants.

If anyone uses this concoction, please message me to let me know if iit works for you. (Maybe try in on the petunias first? And check later in this thread for any updates or corrections.)

As an alternative, you could just add dolomite lime (which is about half and half Ca and Mg) to acid soil.

The calculations. Check my arithmetic!

General Hydroponics CALiMAGic
Directions: (Typical dose recommended by GH) Add 2.5 ml to each 3.79 liters of water.
946 ml per bottle
Bottle weights 1.14 kg

Analysis:
5% Ca
1.5%Mg

Ca
5% of 1140 gram bottle=57.0 grams Ca per bottle
2.5 ml dose/946 ml per bottle= Use 0.0026 bottle per 3.79 liters H20
.0026 bottle *57 g Ca per bottle=0.1482 grams Ca per 3.79 liters H2O
.1482 g Ca /3.79 liters =0.0391 g Ca/liter H2O

CaCO3
CaCO3 weighs 100 grams per mole
Ca weighs 40 grams per mole
CaCO3 is 40/100 = 40% calcium

Dosing Ca:
.0391 gram calcium per liter H20 * 100 g CaCO3/40 g Ca gives 0.09775 gram CaCO3/liter H2O
To make 100X strength solution, add .09775*100=9.775 grams CaCO3 to 1 liter H2O

Mg
1.5% of an 1140 gram bottle=17.1 grams Mg per bottle
2.5 ml dose/946 ml per bottle=0.0026 bottle per 3.79 liters H2O
.0026 bottle *17.1 g Mg per bottle =0.0445 grams Mg per 3.79 liters H2O
.0445 g Mg/3.79 liter H20=0.0117 g Mg/liter H2O

MgCO3
MgCO3 weighs 84 grams per mole
Mg weighs 24 grams per mole
MgCO3 is 24/84=0.2857 or 29% magnesium

Dosing Mg:
.0117 g Mg/liter H2O * 84 g MgCO3/24 g Mg=0.04095 grams MgCO3 per liter H2O
To make 100X strength solution, add .04095*100=4.095 grams MgCO3 to 1 liter H2O

I wonder if cmoon ever looked at all this. LOL. A lazy afternoon wasted...

 

[Troy01]

Your calculations make sense. I applaude you for your scientific approach to mixing your own nutrients. I have to agree with you that the various nutrient mfg gouge you on price when you look at the price of a bag of Epson salt.

I guess I bake more like my Grandmother - a pinch of this and a pinch of that and then see how the girls like it.

 

[Scientific]

Your calculations make sense. I applaude you for your scientific approach to mixing your own nutrients. I have to agree with you that the various nutrient mfg gouge you on price when you look at the price of a bag of Epson salt.

I guess I bake more like my Grandmother - a pinch of this and a pinch of that and then see how the girls like it.

Personally, I use GH FloraSeries, but I try to help out with those who don't have easy access to commercial cannabis nutes.

There's nothing wrong with a pinch of this or that, of course, especially if you enjoy that process, but do bear in mind that for over a hundred years smart scientists with big, well-funded labs and expensive instruments have been spending their lives figuring out the minutiae of plant nutrition so you don't have to!

By analogy, I'm reminded of advice in my ancient Betty Crocker cookbook: "We've tested these recipes in our test kitchen so they're guaranteed to work if you just measure carefully!"

 

[Troy01]

Personally, I use GH FloraSeries, but I try to help out with those who don't have easy access to commercial cannabis nutes.

There's nothing wrong with a pinch of this or that, of course, especially if you enjoy that process, but do bear in mind that for over a hundred years smart scientists with big, well-funded labs and expensive instruments have been spending their lives figuring out the minutiae of plant nutrition so you don't have to!

By analogy, I'm reminded of advice in my ancient Betty Crocker cookbook: "We've tested these recipes in our test kitchen so they're guaranteed to work if you just measure carefully!"

I agree with you on use of good commercial nutes. I have been using Advanced Nutrients 3 part but some of their other advanced nutrients are expensive and don't seem to have much in them.

You have me laughing. My mother swore by Betty Crocker Cook book and I have a copy on my shelf and use it all the time when I want a fail proof recipe. But again even when using BC if I don't have an ingredient ... I put something else in instead that is close... lol

 

[Scientific]

if I don't have an ingredient ... I put something else in instead that is close... lol

Oh man, back in my impoverished bachelor cooking days when I had like six things in the pantry, I came with some really imaginative substitutions. They never worked. OTHOH I had a GF who could look in fridge and see four random things and mix up something good no matter what. Some have got the talent and the intuitive touch, others do better to stick with the formula.

 

[Cmoon]

Re: Supplementing with Calcium and Magnesium Carbonate

Cmoon did indeed look and is mighty thankful he did!....Cheers for the information, it has helped me out so much. I would have spent weeks probably sorting this out when really, the basics are, well,...........basic. Scientific?....You really do know your onions!....(English saying, meaning you know what the hell you are on about) thank you. (Maybe I should send you a bottle of fine Scottish distilled stream water?).

I can't believe it's been nearly 3 weeks since I last wrote anything on here but my plants have gone Mad!.....Day of the triffids type mad! three weeks ago they were all around a foot tall with two starting to bud (after about 6 weeks) & now the same two are looking good with loads of buds but are still only a foot & a half tall, the others are four to five feet tall and show no signs of slowing. Bear in mind I have them indoors in a 2 x 2 x 6ft 'tent'. I did post a couple of pics but I'm not sure how to put the links on this thread? I've done some more tonight and will attempt to put them on here.

I did find a bottle of something called 'callmag' here SHOGUN Calmag - Nutrients & Boosters | GroWell Hydroponics

but even better and easy for me anyway is to buy mineral water and ajdust the calcium & magnesium accordingly. It works a treat. I don't have the figures to hand of the ingredients but I'll stick with it for the time being.......at least for this, my first attempt. I just took some pics and will try to post them on here later tonight (oops or this morning as it's getting on for 2.30am).

I think I explained that when I bought my seeds 10 in all (8 are surviving) they were 3 x Super Skunk,.....2 x Purple Kush,.....and the remaining 3 seeds I just don't know,.....my wife mixed up all the seedlings in their first week and now I just have to judge by the look of them and guess which they are. I do have one which is really odd and if I can post it on here tonight, I will because I hope it ain't a male.

Well thank you Scientist and Wheezze, I'm learning tons with your help!

Many thanks again

PS.
I forgot to ask. I might go down the heat press route rather than tinctures, as I don't smoke, or am I trying to run before I can walk?

 

[Scientific]

Re: Supplementing with Calcium and Magnesium Carbonate

Hi Cmoon. Welcome back!

First off, here are the photo instructions. The process seems a little involved at first, but just remember that most of the options are in fact optional.
Photo Gallery Guide - How to Resize, Upload & Post Photos

> my plants have gone Mad!.....Day of the triffids type mad!
Happy news, and great reference.

> You really do know your onions!
Thanks. I worked with a bunch of Brits for several years and loved learning expressions like that. Y'all speak a parallel branch of Anglish.

That Ca/Mg brew looks like it will do the job.

> my wife mixed up all the seedlings in their first week and now I just have to judge by the look of them and guess which they are
Love it.

> I might go down the heat press route rather than tinctures, as I don't smoke, or am I trying to run before I can walk?
Ha! I think that's the one and only extraction method that I haven't done yet. Are you going to buy a hair straightener and parchment paper? That's what I see everyone using on YouTube. It looks fun and kinda interesting, but like you could waste a lot of herb if you didn't do it right. I guess you could take the leftover squeezins' and soak 'em in alcohol for a kind of second wash.

BTW, my sig file links to photos of how I made oil caps and tincture out of an earlier batch. I wholeheartedly endorse your not smoking. The problem with edibles is that they take a while to hit. I like an alcohol tincture on an empty stomach. The coconut oil extract I made seems to take forever to hit...

I'd love to see some photos if/when you get it figured out...