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Deficency?

Discussion in 'Sick Plants and Problems' started by TheGooey, Mar 13, 2012.

  1. #1 TheGooey, Mar 13, 2012
    Last edited by a moderator: Mar 13, 2012
    Hows it growin everyone?

    So heres my setup...
    4x4 tent
    1k mh about 40 inches above girls
    10 purple arrow clones in 3 gallon pots
    Sentinel evc 2
    Humidity usually about 50-60%
    Temp has been 66 to 79 (switched from 600 threw it off a bit)

    Week 3 veg but coloring started before last weeks transplant.

    Coco with 25% perlite and 1 tbs dolomite lime per gallon

    I though it was goin away but hasnt seemed to yet. Plants are slow growing but still doing well.
    I watered with:
    175ml cns 17 grow
    75 ml silica blast
    75 ml aquashield
    150ml liquid karma
    15ml superthrive
    24 tbs Oregonism xl
    11ml ph down

    Ph 5.85
    Ppm 790

    This was in 15 gallons and each lady got just over 1 gallon.

    What do you think is up? Im considering a light LK foliar feed as most of the new growth looks strong but id like to repair what I can because I want to clone and flip next week.

    And a question also those of you that use fulvic acid and humic acid as ph up/down. What do you use and do you still give the full feed amount and the use it as ph up or down or do you just use it as ph up/down with out addind it otherwise?
     

    Attached Files:

  2. Hey,,, So anyone got any ideas?

    It seems to be spreading a bit and looks like my leaf edges are purple.

    I'm gonna have to flush if its worse tomorrow. I'm not really sure right now.
     
  3. 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.
     
  4. Ok well I ran my profile and it seems way off... Heres what I came up with
    N-96
    P-17
    K-102
    Ca-110
    Mg-15

    If I did this right... Im definitely lacking in phosphorous and magnesium.
    Im thinkin im gonna get some epsom salt to foliar feed and flush with fresh nutes.
    Does that sound right?

    Btw the 5.85 was going in. I never check my runoff in coco but might start doing the slurry test
     
  5. 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.
     
  6. Jellyman, I appreciate your help but I think were both a little confused.

    The numbers I posted are in ppm.

    Why do you think my ph is off? Coco runs from 5.5 to 6.2 as far as I know. Askeds coco guide says to put everything goin in to 5.8 but most growers have found to let ph swing to increase uptake of different nutes.

    Im just trying to follow your line of thinking, I appreciate the help and glad you finally called me out on my nute profile because id tried to run the numbers awhile back but didnt put enough effort in.
     
  7. 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.
     
  8. Scmc! Thanks bud thats exactly what I was looking for. I actually just picked up some epsom salt at the store and will be running to get some cns17 bloom as Im out.

    I ran down the whole nute line and figured out what each product is per 1 ml per gallon. Maybe ill pm you the chart but my last question is,
    Now that I know what 1 ml per gallon is in ppm of each product can I just multiply this number by "x "(ml) and attain my true ppm of solution per gallon?
    I hate algebra but this seems to make sense
     
  9. 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.
     
  10. Thanks again scmc... Im actually running different profiles right now to see what would supposedly work best. The one problem I seem to see is calcium always seems high. Have you noticed this?
    Im basing this on another thread you and I discussed on n,p,k,ca,mg ratios and jorge cervantes' book on pg 262.

    Im using the coco formulas but I noticed the regular cns17 bloom is only 2.0% calcium. Whereas cns17 coco bloom is 2.5%. Im thinking a well thought out mix across their products might be the way to go.

    Im probably way overthinking this now but id let to get it dialed per strain as ill be switching to a larger perpetual setup soon.
     
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