High EC Runoff

Long time (20+ years soil grower), running my 2nd cycle of coco.

First the specs:

Canna Coco w/ 25% perlite
Full line of Canna Nutes minus Boost
H&G Bud XL (in place of Boost)
Magical (Calmag)
Protekt
Great White (once a week)
Molasses
3 gallon smart pots hand watered to waste once a day w/ minimum 20% runoff
26 days 12/12
Feeding at 5.7-5.9 and 1.6-2.2 ec

Potential problem:

Started to notice a bit of leaf curl and some slight burn marks (no leaf tip burns though). Measured the runoff and ph is spot on at 5.8, however ec was measured at 2.6. I read that molasses will screw with your truncheon, but I'm looking for additional opinions. Should I flush and then re-feed at a lower ec or is the runoff ph telling me everything is fine? Like I said I've got growing in soil down to a "t", but wanna make sure I'm doing the right thing in coco.

TIA,

Bunz

Nothing to worry about runoff ec doesn´t tell you anything you can rely on. A high runoff ec is pretty common in cocos.

If treating cocos as you are (Drain to waste + enough runoff), the only thing you got to worry about is, what you feed them and how your plants look.
If they look overfed, just give em less nutes.
If you want to flush, it´s no problem. Just flush with half strenght nutes and feed directly after the flush.

In my opinion Ec 2.2 seems a little bit high for day 26. I never had a strain that needed more than 2.2.

For example growing a 8 week strain with tap water ec 0.7 under 600w
I normally feed em with max. 1.8 of A+B. As soon as flowers appear(normally week 2-3) i add 0.2 Pk 13/14 to raise overall Ec to 2.0. Week 4-6 when they are massively building buds raise to 2.2 ( 1.8 A+b and 0.4 Pk ). After week 6 they get 1.8 A+b + 0.2 Pk again till flushing to prevent budrod caused by too high Pk dosage.

GreenCrack said:

Nothing to worry about runoff ec doesn´t tell you anything you can rely on. A high runoff ec is pretty common in cocos.

If treating cocos as you are (Drain to waste + enough runoff), the only thing you got to worry about is, what you feed them and how your plants look.
If they look overfed, just give em less nutes.
If you want to flush, it´s no problem. Just flush with half strenght nutes and feed directly after the flush.

In my opinion Ec 2.2 seems a little bit high for day 26. I never had a strain that needed more than 2.2.

For example growing a 8 week strain with tap water ec 0.7 under 600w
I normally feed em with max. 1.8 of A+B. As soon as flowers appear(normally week 2-3) i add 0.2 Pk 13/14 to raise overall Ec to 2.0. Week 4-6 when they are massively building buds raise to 2.2 ( 1.8 A+b and 0.4 Pk ). After week 6 they get 1.8 A+b + 0.2 Pk again till flushing to prevent budrod caused by too high Pk dosage.

Click to expand...

I couldn't read more than the first few lines from this post, it is so heinously erroneous.

I suppose I must "humbly" disagree with your here sir.

The runoff EC from coco is EVERYTHING in my garden. I stomp around from site to site trying to help coco growers figure out where they are going wrong.

For starters, the runoff pH from coco is not necessarily the pH of the media. The only reliable way to get the pH of your media is to do a slurry test. Take an adequate amount of coco from as deep down into the planter as you can get and make a muddy "coffee ground" kind of slurry with some distilled or deionized water. Place the pH probe right into slurry. That is the pH of your media. Your runoff of 5.8pH does seem a little low to me. My runoff is usually around 6.2 to 6.5ph and I've never had a pH issue in coco; the media naturally buffers the levels but I have seen acidic coco in the past and I think your runoff level raises enough concern that you should probably do a slurry test to ensure an acidic media pH isn't a contributing issue.

With regards to high runoff, I try to conceptualize what is going on in the media. If I feed 1.0ec, and the runoff is 1.5ec, then to me that means the solution in the media is likely near 2.0ec. Then problems show up. Though, 1.6ec to 2.2ec is a huge range for your solution to be at. I think it is odd you stated it in that way. In week 4 of flowering, in my own garden, I feed at 1.6ec every time. Not 2.0 sometimes, 1.6 other times, maybe 1.8 on the weekends... Every time. Dialed. Knowing what the plants are getting. 1.6ec to 1.7ec would be a much more reasonable range than 1.6ec to 2.2ec.

When the media is washing out more than 30% of the used EC then you have an issue. In other words, if you are using a 1.0ec and the runoff is over 1.3ec then you have salt build up. If you are using 1.5ec and the measurement is over 1.95ec then you have salt build up.

My advice for dealing with buildup is never flushing, always rinsing.

The difference is that when you rinse you are using your basic nutrient formula just dialed back a little bit (watered down) rather than pure water. The reason for this is that Coco will rinse different elements at different rates. Cleaning the coco of cations in that manner will do more harm than good.

What I like to do is take the level I want to be feeding at, let's say 1.8ec, the level that the runoff is at, let's say 2.6ec. The difference between the two is 0.8ec. So, I cut the 1.8ec nutrient solution back by 0.8ec down to make it a 1.0ec solution. This solution still contains all the elements your media requires, and in the proper ratios. I choose to rinse the media with this solution until the runoff is back within a reasonable deviance of where I intend to be. When using the 1.0ec solution I would rinse until the media washed out around 1.3ec.

Then feedings may continue as normal, at 1.8ec, to dial the media back to where it should stay.

Something I should mention is that I find the Canna System to have a problem. When you're running a 2 part system at the same levels the supply of magnesium in relation to the supply of calcium will never change. In addition the Cal-Mag supplements will also lock you into a specific ratio of Calcium to Magnesium with your specific nutrient bottles. The problem I find with this is that I like to run about 1/4 the amount of Mag to Potassium, or around 40ppm to 80ppm of Magnesium depending on the time of growth and the amount of K being supplemented. During late flowering, or even now in mid flower, trying to get that Magnesium in the system without skewing any of your other ratios is damn near impossible.

The answer is 0.05 to 0.1ec of Epsom Salt added to the solution at every feeding. I start in the 2nd week of flowering with about 0.05ec of the salt then I gradually work up to 0.1ec when pushing the boosters in weeks 6 and 7. An occasional Epsom centric foliar spray will go a long way for your plants right now as they fight for the uptake of cations. I also find the Canna system to be a little short on Potassium as well, especially during the transitional stage, and I have used a variety of supplements to manage that issue (Snow Storm Ultra, Potassium Silicates, Deuce-Deuce, Big Bud, and now Uncle John's Blend) and I think you might want to consider adding some products to increase your control over the K+Mag ratios as flowering progresses.

First thing though. Rinse that media down to where you want it.

I find that every gallon of "rinse" will bring the EC down by about 0.15 to 0.2. You'll probably need 3 gallons per planter today, and 3 gallons per planter tomorrow, at 1.0ec, to get them washed out and good to go.

One thing I do need to mention is that you will probably experience diminished yields as a result of this. It is my advice to coco growers to take it easy on their plants in the transitional stage from Veg to Flower. Vegetative growth in coco is very different from flowering, the plant seems to handle a lot of abuse and really high EC levels during veg much better than in flowering. For the first 20 days or so of 12/12 I always suggest running a 1.2ec to 1.4ec with lots of runoff and a little extra Magnesium. This allows growers to hit weeks 4, 5, and 6 with vigor and really ramp things up for the flower sites to thick up. Since you're already in week 4 you have to play catch up to where you could be if you'd taken it a little easier on them the last few weeks. Instead of having a media that is balanced and ready to be super-charged you have a media that is out of balance and that must be refreshed before it can be super charged. This is going to cost you a few days of the a very critical formative period when your flower sites are just coming alive.

Hope for the best.

Your problem is one I have experienced many times myself. My advice comes from about 3 years of practice in coco. Applying 30% to 40% runoff regularly, lowering my transitional EC, and rinsing rather than flushing, has tripled my harvests versus other methods. I encourage you to leave the "I dunno, I just water it, it's a weed, totally easy to grow" kind of advice at the door and join me in the applied conceptualization of what is going on in the media.

please try to remember that there are more ways then 1 of skinning a cat as the saying goes. this applies equally to growing good fat buds in coco. there isn't just 1 way that works. so basically choose the people you listen to by the look of their gardens, the similarity of set ups and then stick with 1 persons advise. otherwise you will mix systems which is what often causes problems. plants like things to be regular, so once you begin a certain way you should continue that way.

you will note that coco can get high ec level run off after a while, as long as the plants are looking strong and healthy this can be ignored, specially when you run to waste. however a flush followed by normal feeding can be beneficial, specially if the plants don't look happy.

i must say that over time i have noticed again and again that more ferts is not always better in coco. actually giving slightly less seems to get better results then giving slightly too much. but there again this is also strain dependent, some nutrient hog strains will be the exception to the rule and only thrive to their fullest when being pushed. the secret is finding out the needs of your strains and getting things just right for them.

if my plants seem troubled i will cut back to basics A+B, zym, and cannaboost.

@Snow Crash
I agree on most what you said, but i´m a bit curious about how you try to maintain a stable ec in the medium.

As i see it, there´s nothing wrong about how you do it, because even if your assumption how runoff ec behaves related to medium ec was wrong, what you do would not harm your plants at all. As rinsing with low ec then feeding again at the desired rate is surely not bad at all even if it would possibly not be neccessary. So i would like to know if you actually confirmed your theory by measuring the ec in the medium.

I have for example seen Plants performing very well at a runoff ec around 4.x. But also have seen plants absolutely overfed due to high feedings without having a increased runoff ec.

Also i observed that the runoff ec can reach spikes within a few days (in my case 3.5 feeding at 2.0 ) and beeing just fine at 2.1 again the next day without increasing runoff, rinsing or flushing.

I never managed to find a easy rule that would explain runoff values in relation to how my plants look and perform.

[theory start]
Nitrogen for example has a mich higher impact on ec than P and K. If i for example got a Plant in Bloom that takes up only small amounts of N. When feeding the cocos would take up much more P and K in relation to N. That would leave me with a completely different ratio in the runoff which may make ec readings unreliable.

To test this, just take a look how much N would be in one Liter of your solution (1.7ec using tap water at 0.7). Take a N only fert, and add this amount to 300ml (30% runoff) tap water. That leaves me with an ec of 2.2.
Of course i don´t know how much of what is actually taken up or released by the coco, and that would not explain values completely out of range, but still makes me doubt the relevance of runoff ec readings.

Or thake hot day, when the plants just take up more water but not much more nutes than usually. Feeding next day would result in cocos that soaks up much more water, but doesn´t need all the nutes you supply. That would result in a runoff with much more nutes concentrated in it than usually.
[/theory end]
I hope i got things about the high cec of cocos right and what i wrote is not complete bullshit.

To sum it up, it seems to me that you are "manually" trying to keep a buffer at a certain level. Nothing wrong about that, because your plants are always supplied with what they need and everything shoud be in perfect range. But as i see it, this buffer also performs pretty well when regulating itself which is one of the advantages cocos has to offer.

Would be great if you could give me more insight on how you came to your conclusions. I would love to know how i can get solid information from my runoff, but myself didn´t find anything i could rely on.

CHEERS

Here's my thoughts behind my method.

I want what is coming out of the media to be as close to what is going into the media as I can get. I use a calculator and the labeled percentages to get a ballpark idea of where the ppm level for each element will be in my solution. By using a good deal of runoff regularly I ensure minimal buildup of any one single element and I ensure that the media is as close to the solution I am using as possible.

This provides me with control over my ratios and accuracy in my diagnosis.

I have also seen plants that appeared to be healthy in >4.0ec (because my EC meter doesn't go past 4.0ec... why would it need to?) only to later go south. Veg and Flowering are totally different also, and a finished plant just doesn't need and cannot handle that many cations.

There's no way to really know what is in the media just by looking at one test. I always measure my runoff and I keep a good diary and loads of data. I'm one of very few growers who actually thinks it is important to keep a good record of what was fed and when, what was collected, and what it tested at. Over time this quantity of data (20 plants over the course of about 140 days adds up to a lot of information) that I can build a kind of relational "model" in my head that helps my mind understand what is going on in the media based on the runoff and based on what I've seen before.

Something interesting I noticed last night as an example:

I fed my plants in the first hour of lights on. The solution used was at roughly 1.3ec. Each planter received 6L of solution and approximately 2500ml of runoff was collected. Most runoff tested between 1.5ec and 1.6ec. Any planter over 1.6ec was rinsed with an additional 2500ml of solution to drop the EC of the media.

After 8 hours I returned for a second feeding (well rooted plants entering their 3rd week of 12/12 in coco). This time I used an ~0.85ec solution and fed each planter 3L. The ~1500ml to 2000ml of runoff collected from every planter was in excess of 1.6ec. Using less food, and a greater ratio of runoff, I managed to get an even higher runoff.

My thoughts on this are that the ebb and flow of elements into and out of the plant will alter the runoff values. While your runoff might seem reasonable when testing right after lights on it may only be the result of the plant taking in elements at the beginning of the cycle. Later on in the day the plant might be sitting in a soup that is too strong and you may have no idea because of when the runoff was taken.

Ultimately it shows that in coco there is no concrete rule when it comes to runoff. Do what works, and keep trying new things until you find something that does. Keep a good diary and it will make the relational understandings easier to deal with. Understanding the EC of the solution in the media is a kind of "fuzzy logic" and it is one of those things that I don't know how to actually teach yet. More of a "you'll figure it out" approach. That's why I suggest copious runoff. Worst case scenario? You wash a little extra nutrients down the drain. When I'm spending $100 on nutrients for a whole grow, and pulling down 500 grams plus... the fuck do I care about $33 in runoff?

Good info snow..
I posted something similar to this in rez's thread..maybe ill get a faster response here though. I'm starting to be a believer in the whole runoff doesn't matter side..but maybe I've just been lucky idk lol..one of my ladies has an extremely high run off..@ 3000 ppm/4.0 ph when I checked it last nite (4 weeks into 12/12 in hempys) Main reason being (I think)that I didn't wash my coco....and honestly haven't checkd its runoff in about 2 weeks cuz she is so healthy and beautiful that I just kinda sit there and scratch my head and go hmmm lol..

That's damn near 6 times as high as what goes in! I use Rez's/heads 6/9..I just dropped the micro so ppms come out to roughly 470..5 somethin with the kb shot.

I look at her and she's telling me she's good so what do I do in this circumstance? Go with my gut cuz I know that's horrible numbers or just wait for her to show something. Ill try and post some pics soon but I'm a little paranoid about that till then plz take my word for it cuz she gorgeous. My plan was to 'rinse' with the 0/9 mix, to avoid possibly losing yield

I'm by no means a coco expert and still a newbie, but I will learn with time, getting everything dialed is important to me as I wanna have the best shit..

I don't need to go over 1.2 - 1.4 ec

jumanji2 said:

Good info snow..
I posted something similar to this in rez's thread..maybe ill get a faster response here though. I'm starting to be a believer in the whole runoff doesn't matter side..but maybe I've just been lucky idk lol..one of my ladies has an extremely high run off..@ 3000 ppm/4.0 ph when I checked it last nite (4 weeks into 12/12 in hempys) Main reason being (I think)that I didn't wash my coco....and honestly haven't checkd its runoff in about 2 weeks cuz she is so healthy and beautiful that I just kinda sit there and scratch my head and go hmmm lol..

That's damn near 6 times as high as what goes in! I use Rez's/heads 6/9..I just dropped the micro so ppms come out to roughly 470..5 somethin with the kb shot.

I look at her and she's telling me she's good so what do I do in this circumstance? Go with my gut cuz I know that's horrible numbers or just wait for her to show something. Ill try and post some pics soon but I'm a little paranoid about that till then plz take my word for it cuz she gorgeous. My plan was to 'rinse' with the 0/9 mix, to avoid possibly losing yield

I'm by no means a coco expert and still a newbie, but I will learn with time, getting everything dialed is important to me as I wanna have the best shit..

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Hempy's are a whole different ballgame, and there's a different set of rules for that system. As far as I can tell with the 6/9 formula it is designed to actually depend on the build up over time to supplement nutrient levels (as 6/9 isn't all that much food) because you use it start to finish.

I stick to around 1.2 to 1.4 ec in the beginning of flowering but by the 6th and 7th week I'm pushing 2.0ec to 2.2ec. Ensuring that there is no residual buildup and that the plants are not burned before cranking up the levels is crucial for my own plants.

I'll be the 1,000th person to say it. Coco is just so versatile, and Cannabis so hardy, that many methods will work. I struggle with low levels of runoff. I keep hearing about people who get like 5%, or never drain off, so I try it... and in flowering I ALWAYS get issue. So... I use runoff. Not a big deal, not much work really, and the end product speaks for itself.

Two things, drop the calmag you shouldn't need it and lower your EC i never go above 2ml per litre with EC 1.2-4 and i still get a slight burn at that sometimes...Peace

Running hempys with heads formula, have never checked run off, Have never had any problems.
I love coco

"Feeding at 5.7-5.9 and 1.6-2.2 ec"

Ph is good but the EC is really high IMHO. I've found that in coco, over the past couple of years, that less is more as gaiusmarius notes above. I found out about a year ago that I get much better results, plant wise and weight wise, if I keep the EC around 1.2. But that's just me and my experience. Anyone can take that for what it's worth.

TO THE OP,

Since you are getting the curl and burns, and such high run-off; I would flush heavily with 1/4 strength nutrients and then work your way back up to full strength over a few days. 1.6-2.2 is not considered full strength. That's over the limit unless you are running lots of lighting.

I would just use canna Coco a/b for now, if that's what you have. A teaspoon of molasses per gallon should be ok also.

Dr. D said:

Two things, drop the calmag you shouldn't need it and lower your EC i never go above 2ml per litre with EC 1.2-4 and i still get a slight burn at that sometimes...Peace

Click to expand...

Dr.D, what's with the suggestion of dropping the calmag? I don't see the OP mentioning at all his water source and if he is by chance using RO water he should be adding calmag, no?

This thread has given me many more ideas on how to think about my coco.

Thanks much! This is awesome thread!

touringfunkband said:

Dr.D, what's with the suggestion of dropping the calmag? I don't see the OP mentioning at all his water source and if he is by chance using RO water he should be adding calmag, no?

Click to expand...

Water source is ro water

touringfunkband said:

Dr.D, what's with the suggestion of dropping the calmag? I don't see the OP mentioning at all his water source and if he is by chance using RO water he should be adding calmag, no?

Click to expand...

Because i didnt realise Bunz was using RO, you shouldn't need to run calmag with Canna nutes and im pretty sure molasses has some cal/mag, and Bunz if you're using RO then you are defo feeding way too much...Peace

very good point Dr D, using 2.2 ec with ro water is way over what i get good results at with most of the strains i've grown.

the nute hungry strains get like ec 1.8 max and thats using tap water with ec 0.25 most of the time i et best results at 1.5 or 1.7 during flowering.

high run off e.c is just your money going down the drain, no debate necessary, the method most people use to grow coco is the one size fits all lay person method, u bascially over feed and then over water to deal with the over feeding, its no deeper folks, yes it works but it shows u dont know what your doing. run coco side by side, one you over feed over water, the other u feed what the plant wants n with minimal run off, plants will look identical or roughly so, again no biggie on wasteing 30 bucks in nutes for one run and wasting water, its up to u. but if a plant has a hi ec, and u keep pouring hi ec nutes on it, what does that say?



you can run twelve gallons through your plants to bring in fresh air, after the first drops past through the bottom holes of your pots n the gases are exchanged anything more is a waste.

Personally i believe run off is necessary with coco especially if you are running Canna wether you are running a high EC or not.
I also wanted to state that measuring run off EC and ph is not the way to get an accurate reading you need to do the 1:1.5 extraction method

1. Take a sample of Coco from the slabs or pots . This can be done with a soil core sampler or a trowel. To get a representative sample the Coco must be collected from as many places as possible.

2. Put the sample in a bowl and determine whether it contains the right amount of moisture. The Coco has the right amount of moisture if moisture disappears between your fingers when you squeeze it . Add demineralised water if necessary and mix the Coco.

3.Take a 250 ml measuring jug and fill it with 150 ml of demineralised water. Add Coco to the 250 ml mark. Fully mix and allow the slurry to settle for at least two hours.

4. Mix again and measure the pH.

5. Filter this material and measure the EC.

It is advisable to perform a 1:1.5 analysis after 3 to 4 weeks. The target values for
EC are between 1.1 and 1.3, for the pH, between 5.3 and 6.2. Very high
EC values increase the risk of
burning symptoms. To limit the risk of burning symptoms, the Coco
can be rinsed with acidified water (pH 5.8: acidify with CANNA pH-GROW).

Peace