Runoff ph and ppm high

Discussion in 'Coco Coir' started by 967, Jan 13, 2012.

  1. The pH of your runoff doesn't really tell you very much. Especially with just a snap shot. The only way to determine if there is an issue with it is to track the pH over time and see if it changes. I have found that my runoff pH is completely inconclusive and not worth really bothering about. As a matter of fact, I don't really fuck with pH in coco at all... The media is too damn good at buffering itself to be that concerned about.

    The key is not to use a great deal of Phosphoric Acid based pH down, like General Hydroponics, in coco. Coco has an affinity for some elements and this particular mixture of media and solution is bad news for the chemistry.

    If the pH runoff of one container is low it could, and I mean hypothetically, could contain a greater deal of buildup. This buildup is washing out and that is skewing the readings of one planter to another. Without an EC meter there's really no way to tell.

    If you are worried about the condition of your plants then my suggestion is to mix up your nutrients as they are suggested for the particular time of growth. Then add in enough tap water to double the size of the solution (half strength but the same npk ratios). Use this solution and collect a few Liters of runoff from each planter to rinse out buildup and establish a healthy charge in the media.

    If you've been using a pH down product using Phosphoric Acid then I strongly recommend dropping it. Organic acids, like Fulvic acid or Citric crystals are inexpensive alternatives to synthetic products. These offer benefits in coco chelating elements for uptake and allowing a natural fluctuation of pH working with the buffer. Nitric Acid is probably the best synthetic pH down option for coco, like that from TechnaFlora.

    With these products it is safe to adjust the pH as low as 5.2 without harm. The weakly bonded organic acids will quickly break down once introduced to the media and they will float right where they should be every time. It's gotten to the point where I add a "splash" of Fulvic acid. I don't even measure it... might be 2-5ml per gallon or there about. It's not worth being concerned about.

    Picking up an EC meter gives you insight into your program but it's not some vital piece of equipment. Find a reliable nutrient program with a good feed schedule and everything else is environmental.
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  2. I can't speak to runoff, as I never bother measuring it. I can say that particularly with my sativas I start seeing signs of magnesium deficiencies around 6 weeks, and find that a teaspoon of epsom salt per gallon in my nutrient every four weeks helps with that.

    I grow 12/12, so six weeks in my case includes the entire "veg" period.
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  3. 1tsp = 5 grams

    5 grams = 5000mg

    Epsom Salt = 9.8% Magnesium

    1 US Gallon = 3.78 liters

    Parts Per Million = mg/L

    Safe ppm range for Magnesium = 15ppm to 65ppm

    (5000mg * 0.098 ) / 3.78L = 129.6mg/L (aka ppm) of Magnesium

    The numbers don't lie. 1 teaspoon of Epsom Salt is easily twice as much Epsom as a plant would need. Include hardness from the tap water, and Magnesium provided in the nutrient program, and this is a recipe for disaster. Most likely causing issues with the uptake of other elements, trading one deficiency for another.

    1/4 teaspoon of Epsom Salt is more than enough. This offers a 30ppm boost and could definitely double the amount of Magnesium in the solution. I recommend about 1/8th teaspoon for the Mag hungry strains on a regular basis for the 12-15ppm increase it offers to the element. Managing a deficiency isn't about slamming your plant with a ridiculous amount of the element. We need to make subtle changes to our solution to reflect the needs of the plant. If "30ppm" of magnesium hasn't been enough then a 50% increase to maybe 45ppm will. Jumping from 30ppm to 160ppm is going to cause more problems than it solves.

    Genuine Magnesium deficiency can be alleviated by a mild Foliar spray. Mix 1/8tsp of Epsom salt in 1L of water with a drop of a biodegradable surfactant like Ivory dish soap, and/or an organic acid like Fulvic. Apply the foliar program to the underside of the leafs at lights on for two consecutive days. Also reduce the nutrient strength by 20% and ensure plenty of runoff.

    Coco specific nutrient programs tend to be extremely Calcium dominated. As the plant transitions from Veg to flowering the nutritional requirements change and a media that is saturated with calcium makes it more difficult for the plant to acquire the magnesium it needs. These elements, along with potassium, compete for uptake with each other and when an imbalance or toxicity is present in the media Magnesium (the least abundant) tends to get locked out. More often than not a Magnesium deficiency has more to do with too much Cal+K than not enough Mg.

    What I prefer to do, just as I enter flowering, is switch to my Bloom formula right from 12/12. Bloom macro nutrients, like CNS17 Bloom, carry less Calcium for a better Ca:Mg ratio for the time of growth. A little extra runoff for the first few days of bloom won't hurt anything and I think it helps remove the buildup from Veg (N+Cal mostly) so that what I feed daily is what the plant has access to, and not the last month of possible buildup.
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  4. Thank you very much, I'll start reducing to 1/2 teaspoon per gallon going forward. This five pound bag of epsom is going to clearly last me the rest of my life! :)
    fuck i always wondered this.... amazing! thank you so fucking much! you're a life changer
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  6. Fuck yeah

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  7. are you growing in coco? if so it should be EVERY day once you have an established rootzone, 10% run off(discarded)
  8. hey mate, are you growing in coco? how often are you feeding and is it to runoff? sounds like a build up to me from over feeding(or a poorly flushed medium before transplant), would explain why the ph's are all different as the heavier feeders will be using up more nutes ect
  9. I had the big pheno of Blue Widow before,It was a good yielder and tasted amazing,the pheno I got this time is way shorter,hope it tastes as good as before though.
  10. I usually run my plants on the farm I work on at 5.6-5.8 and occasionally raise it to 6.0. Usually about twice a week. My plants look great! Weird question but does anyone here never flush or let they’re water run completely through they’re plants? I have never had a problem with salt build up or any problems with ph. I also use just Canna Nutrients and only the part A and B and nothing else. Anybody have any opinions? I’d love to here them. [​IMG]

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  11. I also do not use any perlite!! Very odd from what I here a lot of growers say on here! Let me here your opinions!!

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  12. I only ever used perlite in soil grows,my current grow I have 1 in coco/perlite the rest in coco.
  13. How long into veg are you here? should dabble in some defoliation mate
  14. As coco dries the PH raises. Also, as it dries it is leaving salts behind. IMO you are seeing the result of not watering often enough. I say water coco multiple times a day for this reason.
    edit: its hard to overwater coco, be weary of that advice. treat it like a hydroponic medium, always wet/damp.
  15. If you add up all the feedings you have gave it in the period before flushing then take it away what the run off is will tell you how much it’s eating

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  17. I only go longer than 24 hours after a transplant, i wait for 30% dryback to get the roots searching then water again, once roots are established its minimum of once daily to runoff.
  18. When you say water multiple times a day, you watering to waste every feeding or just the final feed for that day?
  19. Hi Tokeycones, I’m currently in my second grow in coco and this is what I’ve observed in my grow regarding your question. I’ll share a little about my setup for you. I observe my outlet (runoff) EC very closely everyday. My answer for your question is “yes”, water for run off each time! I’ll explain and share what has worked really well for me.

    I’m growing a GSC from Nirvana in a 5 gal smart pot with coco/perlite 70/30. I’ve setup and installed an automatic watering system, which includes a 20 gal reservoir, a 500gph pump, 5/8” irrigation tubing, 1/4” drip irrigation tubing, and six 1 gal/min drip emitters.

    My auto-watering setup feeds my lady 4x’s/day, roughly every 6 hrs ranging from 7 minutes (mid night) up to 13 minutes (mid day) per watering from my nutrient reservoir. I mix approximately 2 weeks worth of nutrient water to be fed to her each and every feeding depending on what stage of growth she’s in. I also hand water her once a week with roughly 32 ounces of the same reservoir nutrient water to ensure good medium saturation and no dry spots left in my coco. I NEVER water plain water (except harvest flushing) or 50% mixes from my nutrient water ever in order to lower my EC; I’ll explain below. Currently my reservoir is mixed with GH’s nutes at an inlet EC of 1200. Note: my outlet (runoff) EC goal is within 300 above my inlet EC, so 1500 in this case. My runoff volume goal is 30% my inlet volume, to save time it’s 288-500 mls of runoff.

    During her stages of growth she’s required a little more and more watering to produce runoff, which is great cause I know she’s taking what I’m throwing at her. As she grows, and she’s grown a lot! I’ve had to increase my watering interval times. For example, the mid day watering was about 6 minutes at the start of flowering. Now, she’s in week 4 and her mid day watering is 13 minutes.

    Now, at times during her growth spurt she’s had a couple consecutive waterings that didn’t provide runoff because she’s taking in more water and nutrients. I’d then adjust my watering intervals and the next runoff would be higher do to a mild build up because there was no runoff for two prior feedings. The highest I’ve seen my runoff EC was 1750. I was curious if I was in trouble, but she took it really well and I corrected it early on too.

    In my case above, EC of 1750, I just hand watered with 32 ounces of nute water (EC 1200 inlet water). The additional water creates runoff water that flushes and feeds at the same time while gently lowering the EC back within my goal. After doing this my outlet EC drops back down to around 1200-1250, and I just sit back and monitor her runoff each watering.

    So wether you’re “watering to waste” or not, know that your EC is affected in either case.

    Now, before I setup my auto-watering I was hand watering once a day. I had learned from an online source to water feed water once a day and water plain pH’d Calimag water every other day. When I was doing this my EC was all over the place! 600 one day, 1200 another, I knew something wasn’t right, but I wasn’t sure what was happening.

    After a lot of research I learned that multiple feeds/water is best for coco. Coco For Cannabis website will provide you with wonderful information about CEC, EC, and the benefits watering multiple times/day. It was awesome learning and observing what happened when I went to auto-waterings with this GSC. My EC was at 600 when I started auto-watering, and it took about a week and a half to get my EC runoff up to 1200. What’s interesting was I did this over a week and a half by allowing very little runoff so my CEC would rise. Once my EC was where I needed it, then I began watering intervals long enough to provide just the right amount (30%) of runoff water each feeding.

    I hope my explanation helps you. Not sure if you’re watering by hand or not, but that got super old for me fast!! I cannot stand mixing and moving water around. I love the freedom having 2 weeks worth of feed water ready and on auto-pilot. Plus her being watered 4x’s/day spoils the heck out of her and she loves it!! :) take care and good luck with your grow

    Here’s a peak at my lady at 4 weeks yesterday :)


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