Improving My Rdwc. Having Major Ph Drop.

Discussion in 'Growing Marijuana Indoors' started by mollytree, Sep 7, 2014.

  1. #1 mollytree, Sep 7, 2014
    Last edited by a moderator: Sep 7, 2014
    [SIZE=medium]System[/SIZE]
    [SIZE=medium]32  3GAL buckets recirculating Deep Water Culture (DWC) with Botanicare 40GAL reservoir- 4 Rows of 8
    Eco264 Pump to include 15 minute on/off timer
    2- 200LPM Air Pumps  with 4IN stones in every bucket (32 Air Stones)Buckets are lifted on blocks about 1.5”, allowing additional water for reservoir
    Buckets hold ~2GAL/bucket; Reservoir holds ~30GAL  (~90-100GAL System)
    6” net pots with Hydroton medium
    [/SIZE]
    [SIZE=medium]Water Chiller[/SIZE]
     
    [SIZE=medium]Nut'z[/SIZE]
    [SIZE=medium]Flora Series Expert Recirculating[/SIZE]
    [SIZE=medium]http://generalhydroponics.com/site/gh/docs/feeding_sched/GH-FloraSeries-REC-Charts.pdf[/SIZE]
    [SIZE=medium]SuperThrive: 1ML/GAL
    Orca: .5ML/GAL
    [/SIZE]
    [SIZE=medium]Silica Blast (Botanicare): 1ML/GAL early veg, 2.5ML/GAL veg/late veg, 5ML/GAL weeks 1-5 flower[/SIZE]
    [SIZE=medium]PPM Week 1: 800 PPM[/SIZE]
    [SIZE=medium]Weeks 2-5 (Depending on Plant): 950 PPM
    PPM Week 1 Flower: 900 PPM; Week 2-3: 1000 PPM; Week 4-5 1100; Week 6: 1200 PPM; Week 7:  1100 PPM; Week 8: Flush
    [/SIZE]
     
    [SIZE=medium]General Grow: Veg
    Air temps stay between 75*-78* (Working on getting an AC, as I'd rather the temps be between 72*-75*)
    [/SIZE]
    [SIZE=medium]Humidity stays between 40-50%[/SIZE]
    [SIZE=medium]T5 Lighting Satellites & a few LED's[/SIZE]
    [SIZE=medium]Water temps in rez: 66*
    Water temp at first entry to root zone: 67*
    [/SIZE]
    [SIZE=medium]Water temp at exit of system: 69*[/SIZE]
     
    [SIZE=medium]Additional Information:[/SIZE]
    [SIZE=medium]20/32 Plants in system came from flowering plants, and have reverted to veg growth.[/SIZE]
    [SIZE=medium]Foliar feeding once/week.[/SIZE]
    [SIZE=medium]50ML/GAL Diamond nectar
    1ML/GAL florialicous plus
    [/SIZE]
    [SIZE=medium]Then i add fresh nut batch till PPM hits 250 
    250 PPM w/ coco wetting agent
    [/SIZE]
     
    [SIZE=medium]There is a total of 8 strains in system[/SIZE]
     
    [SIZE=medium]Questions and Concerns:[/SIZE]
    [SIZE=medium]Why is my pH rapidly dropping after a nutrient change?[/SIZE]
    [SIZE=medium]Roots do look darker than normal, showing more of a beige than a healthy white. I'm thinking it could be a bacteria issue, or perhaps salt build-up due to recent high nutrient levels (close to 1200 PPM). I did a 500 PPM flush for twenty-four hours. I changed the reservoir again, this time replacing nutrients to 950 PPM. My pH is still continuously dropping. I'm putting anywhere between 100-200ML of pH UP into the system/day.  Approximately half of the twenty reverted plants show small leaf growth and big ridges between veins. I've read that Adding organics, sugars, bacteria, and zyme products have shown to create potentially harmful biofilms, hinder pH stability and require more frequent nutrient change outs. Should I drop a lot of my products? [/SIZE]
     

     
  2. #2 TheAnswer121, Sep 7, 2014
    Last edited by a moderator: Sep 7, 2014
    odds are your not checking your ppm fluctuations. sounds like nute mix is off causing a flux in ph.
     
     
    your ppm schedule seems very high. i'm in week 5 of flower and 750ppm
     
    coloring is likely from the nutrients and nothing to worry about.
     
    also, 3 gallon pots are not very big. maybe upgrade to 5 gallons so roots have some breathing room. i can imagine the root ball is taking up a lot of space, which will cause issues.
     
  3. I check my ppm 20 times a day its the same so is me E.C.
    I am very percise to follow my schedule.
     
    PPM i think is to high as well. what are your recomendations for a veg system that has plants 2 3 and 4 weeks old.
    they get cloned in a cloner moved to a site for a week and then into this system.
     
    In my flowering room i do have 5 gallon bucket. this is my veg room. no issues with root ball.
     
  4. #4 TheAnswer121, Sep 7, 2014
    Last edited by a moderator: Sep 7, 2014
    400-500 ppm should suffice
     
    if ppm rises, it's still too high. just dilute with ph'd h2o
     
    if it falls, increase by 100 until you find the sweet spot
     
    my roots generally don't start staining until well into flower, so i can imagine how fast it would occur with such a rich solution
     
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  5. #5 mollytree, Sep 7, 2014
    Last edited by a moderator: Sep 7, 2014
     
    so we both argee to lower PPM.
     
    So my PPM is not moving much at all its my PH that is rapidly droping.
     
    but your saying droping my PPM will FIX my PH?
     
  6. if your ppm is not fluctuating, then you have a different problem. but if you are at 950 ppm 2,3,4 weeks in veg, i guarantee it's an issue.
     
    good luck
     
  7. needing someone more advanced input. Adding organics, sugars, bacteria, and zyme products have shown to create potentially harmful biofilms, hinder pH stability and require more frequent nutrient change outs. Should I drop a lot of my products?  florialicous plus - orca - florablend?
     
     
    \tCurrent Culture H2O's General Recommendations 
    Adjusting pH & EC/ppm: Adding concentrated pH adjusters or nutrients directly to the system may result in extreme plant/root shock. Anything added directly to the system should be diluted to at least 20% and added slowly. For best results pH and EC/ppm adjustments should be done through the top-off reservoir.
     
    Nutrient Considerations: Highly chelated, clean, synthetic nutrients such as our Cultured Solutionsâ„¢ line have proven to work best in water culture both for their pH stability and ability to stay viable in solution for longer periods. Adding organics, sugars, bacteria, and zyme products have shown to create potentially harmful biofilms, hinder pH stability and require more frequent nutrient change outs.
     
    Nutrient Strength: If not using Cultured Solutions™, we typically recommend starting between ¼ and ½ strength of standard nutrient recommendations. When starting with rooted cuttings transplant into the system at 0.3 EC or 200ppm and increase 10-20% per week based on plant performance. **When supercharging aeration levels nutrients should be reduced even further.
     
    Nutrient Change Outs: When plants are feeding and growing normally, full nutrient change outs are beneficial every 14-21 days. If pH levels become unstable or nutrient levels start to rise or stagnate this may be a good indication to do a full or partial change out. When using more complex nutrient recipes or heavy organic inputs more frequent (every 7-10 days) nutrient change outs may be necessary.
     
     
     
  8. #8 Pot Professor Paul, Sep 10, 2014
    Last edited by a moderator: Sep 10, 2014
    what is orca is that a kelp product? if it is black in color then GET RID OF IT!!!! NOTHING BLACK goes in yer rez or it will slime yer zone and create black funk! organics in rez equals problems run salts and good salts at best! yer ph problem is because yer roots are probably toast. just like mine were. i was feeding heavy with organics in a flood n drain week 6 bloom i checked root zone. slime brown/black funk! i was humbolts natural bloom nutrifields ocean mist molasses pure can sugar sugaree ect... dump organics unless yer drain to waste yer rez should be filled at say 5.7 - 6.0 ph for veg at around 580 ppms until transistion to bloom. then increase to 800ppms no more than 1000ppms. at this time u can drop down to 5.6 or 5.7 ph. never go below 5.5ph try to stay between 5.6 and 6.3 its ok to drift i "ride the wave" its a sign your plants are excepting all available nutes on the scale good luck!
     
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  9. Sounds like decent advice
     

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