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my first grow - hydro - 3 weeks into flowering - yellow leaves dry

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    HYDRO my first grow - hydro - 3 weeks into flowering - yellow leaves dry


    I’m new to the forum and new to growing
    I was reading most of the content on growweedeasy and I have to say I worked really good as a guide

    but right now I’m getting problems I can't seem to solve and I’m getting nervous

    hopefully someone can point me to the right direction

    I try to give you as much info as I can... (Sorry for the long text

    My Setup:

    3 bucket RDWC Hydro (7 gallon total) (centre is for pump to buckets and PH&EC measuring, 2nd is for the plant, 3rd is for chiller an refill valve)
    I have also CO2 injection @ 1400ppm
    I use only RO water @ EC 0.12 an base PH of 6.5
    Temp in grow room is constant 87.8°F @daytime with CO2 and 77°F @ night times
    nutrient solution is @ 66°F with chiller
    I’m on 3rd week flowering
    humidity constant @ 45-50% max (getting my dehumidifier next week)
    Nutrition: advanced nutrients (pH Perfect® Base Nutrients) Beginner Level
    Light: Greenception GC9 288Watt (equivalent to 400Watt)
    (5,9 inches): 2450 μmol/m²*s
    (11,81 inches): 1800 μmol/m²*s

    Light height right now: -+ 23.6 in !!

    In fact it's my 3rd try to grow..

    1st time I gave the plant at very early seedling stage a wind burn never recovered... (Closed my tent and touched the vent without realizing.. next day I had the result

    2nd time I gave her a light burn also seedling stage ... way to close... I’m really impressed with the performance of that light…

    so at that point I paid really attention on everything now... and learned from my errors and reading on different places
    Now for the 3rd try that thing grows like crazy I followed the manifold guide... topped 2 times an defoliated to get to my 8 colas
    up that point everything went very smooth but very fast too... nearly too fast for me..
    From the first topping on I also did LST to direct them to the right spots (worked well)
    After the second topping I left the plant 2 weeks in vedge … and then I switched to 12/12 (the plant was really growing fast… and I feared the stretching phase…

    the first day I also switched my led light to flowering phase
    the next day I saw some yellowing in the middle of the plant.. I immediately remembered my burned seedling... so I switched back to veg light (but still on 12/12)
    the plant grows fantastic.. But the older lower leaves are getting more and more yellow...
    all the new grow and the grow not in the middle seems not to be affected
    I still switched the light on flowering light (manufacturer says at latest when you see the first white hairs you should switch! So I did

    so I hung my led from 18 in to 23,62
    I also had my nutrient change (I do that every 7 day complete change)
    I follow directions from the calculator from nutrients at full dose (already for 5 weeks)
    Concerning PH and EC I had “problems” from the beginning on
    I follow the AN at half dose and my EC went to high immediately… an PH got down…
    At the beginning I tried to adjust the ph but it always went down fast… so I had to use insane amount of ph up to adjust it. I tried Tap water, distilled water and finally RO water.. Every time the +- nearly same results
    At that phase I had never any sign of nutrient burn.. and the plant grows really good.. When I do the LST training.. In max 2-3 hours the plant is already upright again …crazy... so I was not to concerned
    But I got really frustrated at a point where I called their support.. a very nice guy explained me that I did some good thing but I shouldn’t mess with the nutrition’s and PH
    His answer in short: use the product like advised otherwise it won’t work like it should…
    When I told him my base EC an what amount of nutrition’s I’m adding.. He calculated and said I should be around 2.4 – 2.5… I was spot on 2.45…
    My PH was 4.35… he said perfect.. Everything between 4 and 8 should work… I explained my all the details in an understandable manner… so I followed his advice…
    He told me even to add nutrition’s again if EC goes down to 1.5 – 2 and then a full change every week
    And I think if the EC would be too high the plant couldn’t survive 7-8 weeks without burning!
    So after all these explanations here my questions/problems J
    • I was training my plant at a point where the whole area I wanted was covered. So now the colas grow fast straight up.. I don’t want to go wider because my light I optimized for 39.37x39.37.. I wanted the canopy of the plant to be 31.49x31.49
      • What should I do? Leave them or try to reroute them? I think It’s also the last week I should do LST (if) and if I should reroute them… where?
    • My plant has yellow leaves in the middle of the Plant (the small grow at the base is perfectly green an growing… the part where the leaves are brown they are dry.. crispy dry
      • Can it be light burn @that distance? Or could it be the consequences of the light burn I think I had the first day of flowering?
      • Why only in the middle ?
    • What about the small grow at the base of the plant… should I leave it there or cut it off?
      • For me it seems buds are forming also already at those places so im not sure what to to…
    Hopefully the pics can say more than my words
    I would really appreciate if someone could help me
    Thanks in advance

    I would leave the branches and grow the them taller. Assuming your LED can handle that type of penetration. That’s odd the yellowing is only in the center. But I do have to say 4.35 is way to low for PH. And 8 is way too high.
    I have great success when I PH down to 5.5 then let it swing up to 6.5 before adjusting it back down again in DWC.
    I like to remove the small growths that form at the base of the stalk. If I miss one past week 4-5 of flower, I’ll let it chill till harvest.
    check out this chart. Shows which nutrients will be absorbed at which PH reading. Optimal being between PH 5.5-6.5 for MJ.
    Attached Files
    Last edited by Toker1; 09-15-2018, 11:10 PM.
    4x4 600w HID empty for summer
    3x3 400w HID with Bruce Banner and Skywalker Kush
    2x2 65w Quantum Board LED with 4 mother strains
    running all simultaneously for a perpetual harvests.


      Hello Evil One, and welcome to the forum!! I'm a hydro grower and I use the AN pH perfect nutes as well. I totally agree with Toker about the pH: I let it fluctuate 5.5-6.5, which is standard for hydroponics. I wonder why the AN guy told you 4.5 was ok...

      I also force the pH to fluctuate throughout the week; I lower it to 5.5 and let it go up.

      Your pictures show some nute burn, I believe. I never get to full strength with AN nutes: I start low and go up very slowly. Right now in the second week of flowering, I'm at around 65% of what they recommend.

      I think your plants could use a 48-hour ph'd water flush; you may have some nute lockout that's causing problems. I flush mine a fairly regular basis. You will see them perk up and explode with growth during and after a 2-day flush.

      Anyone can grow mid grade weed easy. If you want to grow top shelf bud, study hard.

      Growing since July 21, 2016; smoking since 1967
      2 BCNL Roommate hydro boxes w/ 400w COB LEDs, Future Harvest nutes

      Jan 2023: Taking a brief sabbatical


        One thing to understand about PH Perfect products from Advanced Nutrients is that they DO NOT want you to use any kind of PH correction fluids. Their claim is that all of the nutrients in their products are so chelated that a PH swinging from 4.0 to 8.0 is fine; the nutrients will still be absorbed by the plant. They've also told me that using any PH correction fluids will alter the way the "PH Perfect" technology works and nutrient deficiencies may result. Lastly, they told me to not use any organic supplements in my DWC; using such supplements increase the chances of getting root rot.

        In my last DWC grow, I used AN "Connoisseur" series, parts A & B, and it wasn't until I hit flowering and made the mistake of trying to control the PH with large amounts of PH-Up and PH-Down that I ran into problems.

        On my next grow, I plan to use only PH-Perfect nutrients, some silica, and Hisenberg's Tea. As much as it will drive me crazy, I will put the PH-Up and PH-Down away and see what happens. I will still track my PH and EC daily but I will not attempt any corrections. If I see any problems, AN has a 1-800 number and they are usually eager to help.
        JohnC - Colorado


        • Toker1
          Toker1 commented
          Editing a comment
          More than likely they will tell you general plant info that is not specific to MJ. Last I remember, if you bring up that you are talking specificity about MJ, they are quick to shut down the conversation and are very specific that they will not assist with growing MJ. Maybe things have changed in recent years due to recent public enlightenmentabout the subject, but I wouldn’t hold my breath.

        • Shaitantheevil
          Shaitantheevil commented
          Editing a comment
          Hello and thank you for your support/answers i hat the exact same thought's... and i have to say... if i would have my setup like this with constant EC of 2.5 my plant youd burn... but right now beginneing week 5 of flowering it still does fine.... but it also seems i have a nitrogen toxity.... ... so honeltly i don't know what to do...

        • Shaitantheevil
          Shaitantheevil commented
          Editing a comment
          like i said i called them up... i got a really good setup measuring wise... so i got permanent infos about EC an PH... from beginning on i had "problems" to achieve the values everybody is talking about... i had to put a TON of ph up in it... it was for 1 day... then it went down again... he said it's normal.. because the nuts and PH up are fighting against each other... about talking to support he clearly said to forget those values... an forget PH an EC... the nutritions are like "they are always working".. and i have to say up until know the plant devolps good/great)... and the most important point for him was: don't mess with other supplments or PH UP/Down... otherwiese the nutrients would'nt work ass advised.... and i think he's right... he said: people use the products the wrong way.. then blaming us that it's not working.. he said after 3-4 weeks when i'm on full dose really use the full dose an forget the 1,3 EC... i explained to him that anywhere you try to read about EC and PH in cannabis i could'nt find any trace of evidence that 2.5 is ok with PH of 4.4 .... he explained it to me the the solution is "shiedled" and that it releases anytime the right amount of nutrietns to the water... whatever PH value we are onü

          like toker posted the image with the right PH value... he said that their nutrietns are specificly made to work with any PH from 4 to 8 an still give the plant the right amount of nutrients... if everything works well AN could be some magic... because you don't have to pay attention on what you do...

          on the other had it seems i'm beginning to get a nitrogen toxity... that's why i try to get in touch wih them again... i added pics in the first post

        Excellent job on training and your setup. I'm not familiar with AN products or growing under high co2 conditions but it does appear that you have a nutrient imbalance. Perhaps it may benefit doing a trial run on a different nutrient line to see if that helps. I've use GH Flora trio and Megacrop with zero issues.
        5x5 grow space
        900w of Vero's and F-strips
        4-17gal totes self-made UC system.


        • Shaitantheevil
          Shaitantheevil commented
          Editing a comment
          Hello, honestly i think adding CO2 was the best idea i could have... i'm only experiencing and reading postiv things about CO2... it can help in so many ways... i'm happy i did it for the rest i try to reach out to their support... i will keep you informed

        apperently this can be nitrogen toxity...


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