Water Testing Results- Help Interpreting Data

[Cajafiesta]

I figure this may be the most logical place to post this, as I'm growing in soil.

 

Coots recipe soil, to be exact.  Organic, theoretically living soil and all that jazz.  

 

 

 

 

I've had some pretty (seemingly) insurmountable issues over the past year and specifically in the current grow that I have a diary running for.  I've tried everything I can think of with regard to environmental conditions, watering, nutrition etc. 

 

 

I decided to have my water tested. The water composition is as follows:

 

PH 7.39

Alkainity (CaC03) 0ppm

Calcium 7.36ppm

Magnesium 1.6ppm

Sodium 5.67ppm

Phosphorus 1.9ppm

Potassium 1.64ppm

Nitrate (as N) 0.1ppm

 

 

There are a bunch of other listed items, but I figure those are maybe the most relevant.  Happy to provide more details if they're relevant

 

 

I'm looking for some help deciphering what these water test results should mean to me.  My initial suspicion was that I, perhaps, had a cal/mag issue with my tap water. That was more of a hunch based on eliminating most everything else, but I have no idea if I'm incorrect. I'm hoping some of the knowledgeable folks on here can have a gander at my water composition and tell me what they think about the composition and how they'd expect my water to impact dope plants, if at all.

 

 

 

Ironically, I seem to have ignorantly resolved my issues by changing two variables at once. One variable was a change to water and the other was a change to soil.  I'd like to know which solved the issue.  I was pretty convinced my soil was NOT my issue, but I can't be sure. 

 

 

 

We got any water judgers in the house that would be so kind as to chime in?   

 

 

Thanks for any input!

 

 

 

Edited February 26, 2022 by Cajafiesta

[mikeydoughnut]

Just the cal:mag ratio. It appears to be 7:1 (which is me being lazy rounding me maffs up). The golden ratio is 3:1. I believe some kind of mag addition is in order. But for the best advice I’d listen to what @Oldbear has to say. He’s our resident water expert  

Edited February 26, 2022 by mikeydoughnut

[Shumroom]

The ratio of Ca to Mg is 4.6:1

 

Not 7:1 

 

Atb 

 

 

[mikeydoughnut]

I just saw 7 and 1 … it’s out any road …

[Oldbear]

5 hours ago, Cajafiesta said:

PH 7.39

Alkainity (CaC03) 0ppm

Calcium 7.36ppm

Magnesium 1.6ppm

Your calcium and magnesium are very low. You'll need soft water nutes. The golden ratio is 3:1 but with such low levels the soft water feed should balance. Have a chat with Growers Ark or the guys at @One Tree Horticulture about the best solution

 

[ComfortablyDumb]

Alkainity (CaC03) 0ppm

 

You sure that's right ?

[mikeydoughnut]

I think you’re in America if memory serves me correct @Cajafiesta. I’ve just switched to the growers ark nutes oldbear suggested. Trust me it’s be worth the aggravation. I’m sure though there’ll be an option closer to home but if not and they’re happy to ship it, get on it. It’s turning out to be the proverbial dogs knackers for me  

Edited February 26, 2022 by mikeydoughnut

[ukbudz]

@Cajafiesta put your mix recipe up as it will be easier to see what might be lacking and to diagnose the problem. Really shouldn't be getting cal/mag issues in a living soil mix if amended correctly.

 

You might of been better off getting a soil test done to see exactly what is missing.

[MindSoup]

Sorry if this derails the thread but its a question thats been in my head a few times recently. Would there not be a lot of cal/mag in the soil already? And if the microbes do such a good job of regulating the plants uptake would the ratios really matter all that much? 

 

Am I onto something or am I missing the point? 

 

E2A @ukbudz answering my question as I asked it

 

Cheers mate. 

Edited February 26, 2022 by MindSoup

[mysticriver]

Just now, MindSoup said:

Would there not be a lot of cal/mag in the soil already?

Id like to know this too.

 

 

mystic

[MindSoup]

If you're struggling with living soil then the first two questions I would ask about are root temperatures and the size of your pots, I'm finding root temperatures critical to my plants health. Also I really struggle to keep plants healthy in small pots without liquid inputs, as soon as moved to a larger container (35L shared by 4 plants) all the issues seem to have gone away. 

 

E2A my cal/mag ratio is also way off, like 60:1 or something EA2A make that 180:10 ! 

Edited February 26, 2022 by MindSoup

[Cajafiesta]

@Oldbear  Thanks, I'll see if they're willing to chat.  I'm in the US, so not a ton of income earning potential for them with respect to me asking questions, but it's worth a go.  One thing I thought I'd also mention.  I'm not sure constituents go into determining hardness.  I'm aware that calcium and magnesium seem to be the most referenced.  My water test alludes to more components, though.  Maybe I'm not applying the correct concept in how to determine hardness?   

 

Calcium Carbonate (CaC03) is listed at zero ppm.  Cal is listed at 7.36ppm, mag is listed at 1.6ppm.   Hardness ( Ca and Mag) is listed at 24.97ppm and Hardness (total) is listed at 25.51 ppm.   It's likely I'm not understanding the correct way to derive these totals, but the math doesn't make sense to me. 

 

How do I have what combines as a total cal/mag of 8.96ppm but then Hardness (Ca and Mag) lists at 24.97 ppm.   Can you make any sense out of that?

 

 

@ComfortablyDumb That's what the paperwork says.  I have no idea if it's correct or not.  To be honest, I've REALLY been under the assumption that I have hard water, but this test says something drastically different than that.  The results aren't logical to me as far as composition PPM spread across the sampled constituents.  I have a specific level of cal and mag but the test lists hardness (as relative to cal and mag) at a ppm that doesn't match what you get when you add the individual cal/mag ppm numbers.  I'm sort of scratching my head. I get water spots on glass wear, if i put tap water in a humidifier it leaves a chalky white film on the tents filter from mineral buildup.  I'm a bit suspect of the test, almost.  But I'm too ignorant on the subject to make that claim with any confidence. 

 

 Oh, and " Roll Away The Dew, Rollllllll Away The Dewwww" 

 

@mikeydoughnut Thanks, will look into those nutes and see what availability is like in the states.

 

 

@ukbudz a poignant detail indeed.   I intentionally didn't post the soil composition or timeline so that that portion of details wouldn't sway opinion or thoughts. 

 

Here's a sort of condensed timeline of events and characteristics 

 

Beginning of shit show

-Coots style base mix (1/3 peat, 1/3 pearlite, 1/3 bagged compost).  The last 1/3 labeled as compost is actually a mix of several different things.  The total 33% is comprised of about 50% compost, 30% manure and 20% EWC.

-Tap water

-Plants look good and normal until about week 4.  This is when what appears to be NPK or Mag issues creep in.  Leaves begin to show rust spots and color changes in the middle of the leaves.  Begins on older leaves first.  New growth maintains a decent look.  If allowed to continue, rust spots turn into whole-leaf yellowing and eventually death.  Plants are very stunted and flower production is very low.  I let several plants keep going as I couldn't figure out how to fix them.  I'll be lucky if I get 3 grams off of these particular plants that flowered in 1 gallon pots. 

 

Mid shit show desperation

-Attempted to resolve issues by application of nutes in any way I could accomplish.  Bokashi tea with microbes and molasses didn't help.  Liquid fish/kelp didn't help.  Repotting into fresh soil with layered EWC didn't help. Top dressing with EWC didn't help.  Nothing I tried would turn the plants around

 

Advanced-stage shit show desperation

-Switched to using RO water ( to eliminate tap water variables in an effort to figure this out) while water sample was collected and sent off

-Discarded initial "base mix" soil and made a new batch of the same base mix.  This time, added Build A Soil Coots nutrient and mineral amendment kit.  This contains all sorta goodies.  Sprouted barley, kelp, neem cake, crustacean meal, basalt rock dust, gypsum meal, oyster shell flower, Karanja cake.

 

The advanced-stage shit show desperation is where everything got better. It's not perfect, but it's better than it has been in a year or more. I had rooted clones that were only about two weeks into their first pot from the jiffy pellet that began to develop the leaf issues, repotted them into the new amended soil and they resolved their issues.  I have plants that went from seed to flower, and were potted into this new, amended mix at 8 weeks or so.  They had the beginnings of the leaf issues and the resolved themselves.  They're now a couple of weeks into flower and look better than anything I've had in a while.  They dwarf the plants that are ready for the chop that lived their whole life in the initial base mix and are significantly younger. 

 

 

I *think* what's happening here is that (if my water test is to be trusted) I was feeding tap water that's void of cal/mag to plants that had a pretty weak soil blend.  It's as if ( i'm theorizing here) whatever amount of Mag was present in the initial base mix was consumed at about week 4 and the plants couldn't be turned around with what I was doing.  That would support logic, as I wasn't trying to chase a magnesium deficiency.  I was trying to treat an NPK deficiency.  As i understand it, a Mg deficiency would cause an NPK deficiency, but treated it as an NPK deficiency isn't relevant because the Mg is causing lockout.  The NPK may very well be present, but it can't be used.  So treating it as a true NPK issue would get me nowhere.  Which is exactly how this played out.  Mg is making sense, but I still don't know if that's the correct answer. Seems to be coming to that, judging by what folks have to say about the water test. 

 

@MindSoup There were certainly environment issues along the way, and they added variables to this "situation" that really had me chasing my tail.  But I backed off and started stupid.  Fixed all the simple, controllable issues with environment months ago.  Root temps are monitored and controlled, temps and humidity are within range, silly shit like light leaks etc aren't of concern. There's no question I had root temp issues that were out of line on both ends of the cold/hot spectrum, but those are pretty under control now.   I'm also in small pots, but I'm not willing to go to a large pot at this point in time.  I have a lot of different plants and varieties that I'm looking through for my own curiosity.  I've weeded out the males, but I still have probably 20 plants in different stages of use.  Some seedlings, some new clones, some older clones that are maturing into mothers, some in flower, some in veg.  Some landrace sativas, some modern hybrids, some older hybrids.  It's a shit soup of plants that are all at different stages and have different intended "paths of life" so to speak.  

 

 

 

The more I put pieces together, this is sort of really screaming magnesium to me.  The chlorosis starting on the center of the older leaves, maturing to rust spots that grow and the leaf yellows the more the rust spots grow. leaf tips eventually die and the whole leaf eventually gets dead.  This is only present on OLD growth until the middle-end stages of flower and then it manifests in sugar leaves etc. 

 

In ages past, I had the same symptoms in bagged organic potting soil ( this time period has not yet been mentioned on here) using tap water.  This still lines up with logic.  Low Mg water, non-aggressive soil that was amended with a gentle hand using organic teas etc.  In that old scenario I would conceptualize that the Mg deficiency would still be present due to water composition.  

 

 

 

 

 

 

I probably need a soil test now.  Or some sort of pills that make me not worry so that I can just accept that whatever I've done has improved the plants drastically and that has to be "good enough" for me. 

 

 

But I'm not good at that.  I always need to know the "how and why" of everything.  This situation is no exception to that character trait of mine.

 

 

 

 

 

 

 

Thanks so much, everyone, for the input so far.  This has been good info.  Keep it coming, if you actually made it all the way through this Saturday morning novel I've written here. 

[MindSoup]

When you say coots mix, did you add the neem, crustacean meal, basalt etc? Or just 1/3:1/3:1/3 

[Cajafiesta]

12 minutes ago, MindSoup said:

When you say coots mix, did you add the neem, crustacean meal, basalt etc? Or just 1/3:1/3:1/3 

The answer to that depends on what iteration we're talking about and where on the timeline we're referencing.  Look at the previous post I made and read the bold headers.  That shows where I made the change to soil and what the change was. 

 

 

In short, the answer is "no but then yes."

 

If you're going where I think you're going with that question, you're probably on the right track.  I think the overall issue seems to be a lack of Mg, however that comes to be.  Initial base mix may have been Mg poor and tap water was Mg poor.  Switching to Ro water and new, amended base mix likely added Mg content via soil amendments. That may be the answer as to why the plant health improved.  IF that's what has happened, I gotta figure out how to ensure adequate Mg and appropriate Cal/Mg ratio can be maintained organically

Edited February 26, 2022 by Cajafiesta
spelling and shit

[MindSoup]

Yeah that would be it, catching up is hard especially in a small pot.