chillin like a villain
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- Oct 6, 2016
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- Whatever s in my jars
I've been pretty diligent about calibrating both my TDS meter and my ph pen. It is very confusing because one article says you can't add too much Calmag and another says be careful and then another says maybe it's a Phosphorus problem... I initially thought that keeping PH in the reservoir towards the 5.5 5.6 end was potentially making the calcium and magnesium unavailable so I have since raised it to the 6.2 range. I think one of my major issues is that I am trying to scale down the nutes based off a feed schedule for photo's. The other side of this is that the time frame is waaaay condensed so trying to match a 10 or 11 week grow off a 16 to 18 week schedule is confusing...where do they correlate and where do I titrate based on age????? I keep testing and try and this one is better than the last run so....I will back off the calmag....but keep the PK13/14?Well it looks like too much of something or a PH problem. I am working on getting lab equipment so I can figure out the plague we have in autos. I cannot prevent this in my own grows and I just do not know where we are going wrong. I know that the balance in our nutrients is the cause and often for new growers it is too much Cal-mag. I am very careful and still get it. The good thing is it does not stop us from getting a good crop.
I really thought I was hot on the trail and made some changes to my nutrient blend and damn I still got some?
Make sure your PH pen is calibrated and back off on the cal-mag. I will know more in the next few grows as I test the shit out of everything.
Point of clarification - some of the ppm levels in your table are listed as elemental (eg. only the S in SO4 counts), but others are not listed as elemental. What exactly is included in the PPM calculations for these other compounds?Based on my research this is a good starting point for nutrient balance but there is too much latitude. I have stayed in these and still have symptomatic leaves. For sure outside of these ranges you will have trouble. This chart is in weight/l not EC.
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Now about the Calcium thing. Most soil vendors put calcium in as part of the base (long lasting dolomite lime). Coco should be washed and precharged by you or the vendor. Then most nutrient lines have calcium in the base nutrients. In coco you should use nutrients designed for coco and it will have calcium in it at the rate for coco. Then if you use tap water to fertigate with it will have from a little to too much - 100PPMs+ of calcium.
Then we get a new grower with a bottle of Cal-Mag in his/her hand. So you see how easy it is to end up with too much.
That is not the only thing that can cause symptomatic leaves. RH/temp can cause it also - VPD out of range.
Not is not easy being a farmer. Every crop you get across the finish line is a winner.
Those are ION that the plant can utilize. The chart is not in EC. It is in weight of ION per liter.Point of clarification - some of the ppm levels in your table are listed as elemental (eg. only the S in SO4 counts), but others are not listed as elemental. What exactly is included in the PPM calculations for these other compounds?
Thanks for all your efforts with this MOG, you are helping a lot of people.
Sorry I was not clearer with my question - I understand what the ppm refers to, weight of the substance per volume of nute mix. What I am not sure of is why the term elemental is not used for all the nutrient ions in the list. If S is listed as elemental ppm to exclude the weight of the oxygen, why is Molybdate not listed the same way?Those are ION that the plant can utilize. The chart is not in EC. It is in weight of ION per liter.
I believe that as opposed to just an ION the form absorbed by the plant is the element itself. I am not a chemist because I do not want to go down that rabbit hole. You have my permission to venture there.Sorry I was not clearer with my question - I understand what the ppm refers to, weight of the substance per volume of nute mix. What I am not sure of is why the term elemental is not used for all the nutrient ions in the list. If S is listed as elemental ppm to exclude the weight of the oxygen, why is Molybdate not listed the same way?
I'm not trying to pick nits, just trying to understand exactly how the calculations work. For my next grow, I may use a spreadsheet to calculate exactly what my nute mix is during the grow, and the data that you present here will help a lot - if I can make the appropriate calculations from my nute specs. Garbage in, garbage out as the saying goes.