Deficency?

Is that 5.85 the reading of the soil or the liquids & how did you test it?

There also appears to be another issue that could be a deficiency. So I don't have to figure the total NPK of all the many products you're using, would you please provide an NPK of the nutrient solution you give them.

Pics from the side showing the lower leaves of the most problematic plant(s) might help.

 

The NPK represents the percentage of each macronutrient in the fertilizer, so obviously you can't have over 100 of anything. You could use the average of each of the three macronutrients. For example, 2-2-2 fertilizer mixed equally with 6-6-6 fertilizer makes a 4-4-4 fertilizer. It gets more complicated when considering the concentration of each that is used. I should have explained better- too much pot I guess.

All that aside, what you've posted is enough to get an idea of what's going on. I mentioned pics showing the lowest leaves because nutrient burn starts on the leaves closest to the ground. Unless the problem is worse on the oldest & lowest leaves, you appear to have a combination of Phosphorus deficiency and incorrect pH.

You can test the soil pH by getting pure water & verifying its pH. Water the plants well and allow them to sit for at least an hour. Then, squeeze out some water & test it. You can usually accomplish this by pressing on the soil surface and collecting the runoff.

Flushing washes away nutrients and should only be done when there's a toxicity in the substrate or as the last watering before harvest.

PH adjuster can be added to fertilizer solutions if needed.

 

Your calculations look about right.

I agree the issue looks to be a kind of Phosphorus, pH, maybe Calcium thing. This could the be the result of two separate processes which are working against you.

If the media has gone pretty dry, maybe a week ago or so, then when it dried phosphorus precipitated as a salt (possibly with the excess calcium retained in the coco). This caused a lockout issue.

Silicon supplements can also cause a precipitation of Phosphate in solution.

Given the low amount of phosphorus available in the solution to begin with, then factor in the high amount of silicon and potentially a dry period contributing to lockout, and I think that could be your answer to where the problem has come from.

The key here is to not over do it. I would begin using CNS17 Coco/Soil Bloom at 5ml/gallon in addition to the Grow you are using already. This adds 26-23-47 to the profile and should help offset some of the changes I am making. I would keep the Liquid Karma at 10ml/gallon, I would decrease the Silicon to 2.5ml/gallon, I would decrease the AquaShield to 2.5ml/gallon, I would discontinue SuperThrive and Oregonism XL, and this should reduce the amount of pH Down you are using. Then, to supplement the magnesium I would add 1/8th teaspoon per gallon for a 15ppm increase (which, when you think about it, is a pretty large percentage of change for that one element at this stage).

This should increase the phosphorus and nitrogen, balance the cal-mag levels, keep the potassium in the right ratio, and cut down on all the hormones and whatnot in the system for a bit.

The look of your plants is a little common for this stage of life post-transplant. I think you identified a shortage in your nutrient plan and that it would be wise to address the shortage. The key is to get the ratios right where you want them in the solution and to not over-do-it thinking that a bunch of P-Mag is the solution. Slow and steady wins the race hombre.

 

You can never have a true ppm of the solution because we simply do not know what is actually in the nutrient product, only what is "guaranteed" to be in there. Inevitably there will be more...

PPM calculations are a relational tool. You get some levels, work with some ratios, and use the concrete values you can find. This is an abstract idea. Over time you can see what the numbers tell you, more of this or less of that, alter a ratio here or there, and it helps fine tune a system.

It is good to have the calculations done. What I do is take the (# ml)*(label %)*2.654*modifier=ppm. Phosphorus modifier is 0.43. Potassium modifier is 0.84. You can do it your way though, that's fine.

Just remember what you see is the bare minimum in your solution. You do have more, and you don't know how much more, but having accumulated data over a period of time will give you insight into which system needs what supplement based on the calculations. I prefer to use my Calculations to dial in my ratios, and my EC meter to figure out the strength of my solution. Typically the final strength EC of the solution measures at ~150% of the predicted levels based on the labels when running multiple nutrients.

With CNS17 you can basically follow the labels for success but every phenotype and grow room will have quirks that need to be handled. Many growers I know of depend heavily on the CNS17 Bloom as the backbone of their nutrient system, using the Grow or the Ripe (depending on time of life) to supplement with more Nitrogen or more PK.