Why is runoff EC spiking?

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E

Enzo

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When runoff is higher than your feeding EC, it means your plant is not eating all the nutes you are providing so it builds up. Remedy is to flush with pH water until EC is around 800ppm. Then feed at a lower ppm than you were before.
this isn’t always the case and very often incorrect. Yes higher medium ec means the plants are not eating nutrients at the same frequency and ratio as your feeding. But a spike in ec is not usually the plants doing. Ec spikes are contributed to water content going down faster than nutrient uptake is happening. Wether do to the plant sucking up water or evaporation. When feeding coco it is our job to regulate this keeping water content in check which in turn will manage your EC.

The second issue with your statement is flushing with pH balance water. In coco you never wanna do this. Because Coco has a cat-ion exchange rate higher than most medium it naturally will latch on to magnesium and potassium. This action makes it so that even when you’re feeding nutrients into your medium the plant will not have access to 100% of the magnesium and potassium you are feeding because the coco will hold onto some of it. Flushing coco with only ph balanced water will most definitely mess up the cat-ion exchange and nutrient balance in your medium causing lockout and deficiency. If you ever flush I recommend flushing with the exact ec you want your plant to be at u til input ec = output ec. That is a reset.
 
Peat_Phreak

Peat_Phreak

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My comment was based on using peat. Didn't know coco was different. Flushing a high EC runoff in peat down to 800ppm with pH water has worked 100% of the time for me. YMMV.
 
E

Enzo

17
3
This morning runoff went down to 1700, but I had dropped the input to 1200. I have a bit of opportunity here to do some experimentation.

First - channeling of runoff - indeed for 30 seconds the halo drippers don't drip, they have a pretty fast little stream there. I have two options here to mitigate that.
-I have a ball valve on the input side that sits in front of the plants. It's wide open, but I could dial in a restriction to slow the stream down, then double the watering time to make up for it. Problem here is the inability to get any measurements of the water coming in. I cannot take the halos out of the put because the base of the plants is much bigger than the gap in the halo. I'll have to cut down the plants to get those halos off. However, I could pull the hose coming out of that ball valve, measure the unrestricted flow, the dial in a restriction that cuts the input in half, and start over figuring how long the watering cycle should last.

Second - dissipate the water under the halos more effectively. The halos consist of a plastic ring with more than two dozen tiny little holes in the bottom. They tend to spead the water pretty well as-is, but perhaps I should try to put something between the halos and the coco to diffuse the water more evenly. I'm thinking some sort of fibrous mat here, but haven't come up with an idea for the right material. Possibly I could simply cut up an old towel to the shape of the pot and lay it on top of the coco, under the halo. I really like this idea as it sounds like it would perfectly distribute water in the pots, but ... expect the unexpected. Wondering if anyone else tried something like this?

Third - I could most easily double the amount of feedings per day and reduce the watering time per runoff amount. My timer can be programmed up to 20 on/off events. But I lack a schedule for watering more than 5x daily.

Fourth - I could do some sort of flush, one time, by hand or by dumping the whole reservoir. I'm inclined to try this via hand-watering, and I have a flush product called FloraKleen I've never tried.

1st channeling. It sounds like the rate at which your dripper‘s are dripping may be too fast depending on the pressure output of those dripper‘s.

You have two options.

1. You can use your check valve which I also have an also use. The ones I have are floraflex ball valves with handles and they work extremely well. I have those completely gutted with no inserts and i adjust the handle to the appropriate output needed for my plants. I do this for two reasons. One because the inserts tend to get clogged when using anything with organics in your nutrients solution i.e. molasses, kelp and other things. The second reason is because not every strain is the same And some strains have larger dry backs than others requiring slightly more nutrient solution within the same timeframe.

2. you could go to your Home Depot or garden store and get weed blocker. It’s a black mesh that comes in a roll that you use in your outdoor gardens to put in the flowerbeds. It’s kind of like nylon and makes it so water can penetrate but weeds cannot grow through it. If you lay something like this over your Coco under your dripper it would defuse the stream coming out of your dripper‘s and may allow for better saturation however this option depending on how fast your dripper‘s are dripping May cause an overflow as they may not wick as quick as the dripper‘s drip out. They also make coco mat that could work as well.

2. feedings. Remember you can have as many feedings as you want. Five, 10, 20. You can’t overwater Coco as every time you drip on it you’re also bringing oxygen into the root zone. However Coco does not prefer to remain saturated, you have to have some amount of dry back. My watering schedule goes like this. Lights on at 2 PM, first watering for 30 seconds at 4 PM until I get to field capacity. Dry back until 7 PM. Feeding for eight seconds to reach field capacity. Dry back till 10 PM. Feeding for 8 seconds till I reach field capacity. Dry back till 1 am Feeding for eight seconds. Lights out at 2am. Dry back till lights on at 2 pm. Repeat. If my dry back started exceeding my target water content level then I would start those feedings an hour earlier and add another feeding on the end.

3. flushing. From time to time I will flush my plants especially if I leave for a week or so and come back and have larger dry backs and have to adjust my irrigation cycle. If I do so then I just turn on my pump and let my reservoir flow until my target ec has been reached and then I resume my irrigation strategy. When I do this flush I collect my runoff and dump it back into my res to reuse. This last step is just something I do personally as I don’t like wasting water and nutrients solution and since I just flushed however many gallons through the plants the amount of uptake is minimal and my nutrient solution reservoir is barely affected. This is a personal preference and I don’t necessarily recommend it for every grow.
 
phxazcraig

phxazcraig

519
93
Ok, I'm trying a modified flush technique. First, my lights went on at 10am and first water happened 5 minutes later. Runoff into the bucket was 1700+ out, 1200 in.

So....I looked in the reservoir and saw about 3 gallons left. So I just turned the pump on and drained the entire reservoir. I got probably 100% runoff. Pic below.

I then measured the runoff at 1600+ EC, and pH of 5.7. I then added 2 gallons of RO water to bring the EC down to 1000, and a dash of pH UP to get the pH to 6.0. I then poured all 5 gallons back into the reservoir and pumped it empty again. It's draining now. EC coming out of pot is 1200 or so, and dropping

Here is the first reservoir dump runoff amount.
20220318 101739


Here's what the halos look like in action. I could not find any dry channels in any pot with my moisture meter. I rule out channeling at the point.
20220318 102917


Measuring EC at a pot.
20220318 103059


Result is I've pumped more than 7 gallons thru these 4 pots this morning. EC has dropped to 1350.
 
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E

Enzo

17
3
Ok, I'm trying a modified flush technique. First, my lights went on at 10am and first water happened 5 minutes later. Runoff into the bucket was 1700+ out, 1200 in.

So....I looked in the reservoir and saw about 3 gallons left. So I just turned the pump on and drained the entire reservoir. I got probably 100% runoff. Pic below.

I then measured the runoff at 1600+ EC, and pH of 5.7. I then added 2 gallons of RO water to bring the EC down to 1000, and a dash of pH UP to get the pH to 6.0. I then poured all 5 gallons back into the reservoir and pumped it empty again. It's draining now. EC coming out of pot is 1200 or so, and dropping

Here is the first reservoir dump runoff amount.
View attachment 1227143

Here's what the halos look like in action. I could not find any dry channels in any pot with my moisture meter. I rule out channeling at the point.
View attachment 1227147

Measuring EC at a pot. View attachment 1227148

Result is I've pumped more than 7 gallons thru these 4 pots this morning. EC has dropped to 1350.
All this looks and sounds good. The one thing I notice now that I’ve seen pictures is you are using “large air-pot” root pruning pots. There’s are amazing when using soil, soilless or peat. They are meant to grow large plants and root prune. The Problem with them is all the holes in the pots on the side. Two things happen with those, one is the root pruning situation. This is awesome for growing in soil creating new fresh tips and making it so your pot never gets root bound by wrapping round and round the pot. However I find in coco grows this is not what you want. You want your roots to continue growth and be available to suck up as much a possible. Bigger root = bigger fruits. As a matter a fact smaller pots dry back faster, requiring shorter feeds more frequently creating many cycles of dry,wet,dry, wet = awesome!!!

The other issue is with all the holes on the side of the pot when you water water takes the path of least resistance when traveling. This means that as water runs through the top of your Coco and moves to the bottom of the Coco once more while water is coming in water is coming out the bottom but also the sides of the pot which makes it more difficult for you to flush excess nutes to runoff. This means you have to put in a lot more water in order to get your root zone EC down and is probably the reason why you it seems you poured so much in. unfortunately for that situation there’s not much you can do with your current grow besides turning the pressure on your drippers down substantially. The slower the flow the better wicking action you’ll get the more saturated your media will get and the more excess nutrients will run out the bottom in your runoff as opposed to water just running out the sides.

I find I love using those air pots for my mothers that I keep in soil. This allows for great watering, root pruning as well as drying the soil. Since all those holes are there the outside of your Coco is drying up relatively quickly every watering.

The plant in my picture is 4 weeks from clone popping roots and is on day 8 of flower. Not the best example of root growth but you get the picture. It’s also in less than 1 gal of coco.
 
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B7AC03D3 3DC7 4379 BE63 F3A37F9A127C
phxazcraig

phxazcraig

519
93
After the first day or two, I've never observed water running out of the side holes...

Considering the data, I don't think I have any dry spots in the media. I've stuck a moisture meter in all the pots at various depths and locations. Coco is wet everywhere.

Let's not forget the plants. They seem clueless of any EC problem.

I can grab a watering can and dump more water thru but I think the watering is even. I have zero evidence to the contrary.
 
E

Enzo

17
3
After the first day or two, I've never observed water running out of the side holes...

Considering the data, I don't think I have any dry spots in the media. I've stuck a moisture meter in all the pots at various depths and locations. Coco is wet everywhere.

Let's not forget the plants. They seem clueless of any EC problem.

I can grab a watering can and dump more water thru but I think the watering is even. I have zero evidence to the contrary.
I have not said you have dry spots. I’m simply stating that water takes the path of least resistance. So if you think of all the media in your pot as being 100% and you’re running water through that pot to flush there is a lot of media to flush out and water will flow where it’s easiest first effectively flushing 70% of the media more easily and the remaining last.

also if you cut a slit into your pot and measure your water content in different areas of the pot, meaning the bottom third, the middle third, the top third you’ll notice that the water content varies drastically between the measurement spots having more water content on bottom than on top this naturally will also have a different EC value. lower in bottom of your pot to higher on top.

But none of that matters right now as your plants I’m sure or healthy and slight spikes and dips and EC will in no way affect or plant negatively unless they are drastic swings in the upwards direction. I suggest keep doing what you’re doing just making sure you’re getting dry backs between irrigations and do a little research to possibly changing the pots you flower in to a standard 1-3 gallon. The smaller the pot the easier to irrigate, flush and get dry backs. My largest yields and highest quality plants have been grown with smaller pots/less media and more irrigation’s. Fabric pots are awesome if you like the root pruning your aro pots give. Best of both worlds and you can grow monsters in 1 gal fabric pots dripping multiple times a day. For example I run 16 plants per 5x5, cropping every 3 months and average 60 grams a sq ft on hlg550’s
 
dbrzz

dbrzz

159
43
I've been watching my runoff EC all grow, and until flowering, it was always quite a bit lower than input.

Until I hit flowering. Why?

Now, despite adding longer watering times to get perhaps 40% runoff, my EC is 600 higher than input - hit 2000 for an input of 1450 last night.

I'm growing in coco/perlite, 5x daily watering. Plants just finished 4th week since 12/12 flip, and they generally look very healthy. When the EC started rising I noticed a small bit of tip burn.so I backed off on EC for a week, and the tip burn went almost all the way away, but not quite. That was an EC over 1200 or so. But after a bit of a drop EC still went up. When it hit 700 points higher than input I added more time to each watering, to get 40% (or more) runoff. EC dropped for a bit, but now is rising again. Last night I threw some RO water into the reservoir to dilute EC to 1200, and EC dropped 100 points today. This crop has done well on lower EC, so I think maybe I'll just keep it lower.

In the meantime, let's speculate, unless you know what's going on here.

I changed a couple of things when I flipped to flower. Around that time I started putting H2O2 into the reservoir. I also changed the nutrient ratio (per GH mid-level charts) and I started using Floralicious and Liquid Koolbloom. The LED power has been OK or a bit high throughout. I kept PAR above 700 through final veg and am up to 1000 or more now, because of plants crowding the light.

I'm wondering why the EC keeps building in two ways:
1. Something in the nutes is not being absorbed and is building up. (I'm wondering about Floralicious). Also note flushing out much.
2. My plants are simply not eating the nutes like they were before they lost 6 hours of light.
3. Something in the pots other than my plants was eating (processing?) nutes and is not now - perhaps good microbes killed by the H2O2?

And - should I do some sort of flush, perhaps RO water with just cal/mag? Water with that continuously until EC comes down a bunch?
Hydrogen peroxide will kill good bacteria as well as bad.
 
phxazcraig

phxazcraig

519
93
Hydrogen peroxide will kill good bacteria as well as bad.
Yes, but I don't think it is affecting the runoff. I've left it off rge last 3 reservoir changes in any case.

I started this grow with some old foxfarm nutes that weren't necessarily for hydro, and I think the h2o2 cleaned up some reservoir issues resulting from that.
 
phxazcraig

phxazcraig

519
93
I have not said you have dry spots. I’m simply stating that water takes the path of least resistance. So if you think of all the media in your pot as being 100% and you’re running water through that pot to flush there is a lot of media to flush out and water will flow where it’s easiest first effectively flushing 70% of the media more easily and the remaining last.

also if you cut a slit into your pot and measure your water content in different areas of the pot, meaning the bottom third, the middle third, the top third you’ll notice that the water content varies drastically between the measurement spots .
What sort of meter? I've used the standard moisture meter everyone has and jammed the probes at all different parts of the pot. Says saturated in all cases.

Also, after the water comes in and shuts off, it's a couple of minutes before the runoff begins.

The pots are 3.5 gallons. I'm following the cocoforcannabis build instructions very closely.

I've used fabric pots before for soil, both 3 and 5 gallons. These air pots seem good. No way of judging between them at this point.

On that final flush, I put in 5 gallons and got back 4.9. Took 15 minutes to drain. EC still 200 points high.

I've mixed up a new batch of nutes using the same chart as before. But this time I added another 3 gallons or so of RO water to bring the EC down to 1200. I may add another watering and shorten the amounts a bit. I don't need 30 to 40% runoff.
 
E

Enzo

17
3
I use an aroya Solus that I linked above. It reads ec and water content and streams via Bluetooth to an app on your phone. It’s a very dope product.
here is there YouTube. They have so many videos about crop steering. Maybe some of this will interest you.
 
jguit

jguit

Supporter
906
143
2. feedings. Remember you can have as many feedings as you want. Five, 10, 20. You can’t overwater Coco as every time you drip on it you’re also bringing oxygen into the root zone. However Coco does not prefer to remain saturated, you have to have some amount of dry back. My watering schedule goes like this. Lights on at 2 PM, first watering for 30 seconds at 4 PM until I get to field capacity. Dry back until 7 PM. Feeding for eight seconds to reach field capacity. Dry back till 10 PM. Feeding for 8 seconds till I reach field capacity. Dry back till 1 am Feeding for eight seconds. Lights out at 2am. Dry back till lights on at 2 pm. Repeat. If my dry back started exceeding my target water content level then I would start those feedings an hour earlier and add another feeding on the end.
What steering method is this? Unless i'm missing something, I'm not sure i see the difference between this and just doing regular feeds at 3 hour intervals. How much time in between your 8 second feeds to reach your field capacity target before dryback?

I'm trying to look at this like the typical steering methods you see in rockwool.

Phase 1 (2h after lights on slowly reach drain), phase 2 (maintain WC, more frequent shots for vegetative and less freq shots/dry backs for generative), phase 3 (lights off dryback)
 
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E

Enzo

17
3
What steering method is this? Unless i'm missing something, I'm not sure i see the difference between this and just doing regular feeds at 3 hour intervals. How much time in between your 8 second feeds to reach your field capacity target before dryback?

I'm trying to look at this like the typical steering methods you see in rockwool.

Phase 1 (2h after lights on slowly reach drain), phase 2 (maintain WC, more frequent shots for vegative and less freq shots and more dry backs for generative), phase 3 (lights off dryback)
It’s currently generative and I’m feeding based off of my plants cycles, not a specific schedule. It’s about every 2-3 hours after field capacity I dry back from 53-54% wc to about 41-42% at around 2.8ec. And I use floraflex nutes and irrigation strategies with aroya monitoring telling me when the plant has reached 42% wc. Then I water.
 
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E

Enzo

17
3
What steering method is this? Unless i'm missing something, I'm not sure i see the difference between this and just doing regular feeds at 3 hour intervals. How much time in between your 8 second feeds to reach your field capacity target before dryback?

I'm trying to look at this like the typical steering methods you see in rockwool.

Phase 1 (2h after lights on slowly reach drain), phase 2 (maintain WC, more frequent shots for vegetative and less freq shots/dry backs for generative), phase 3 (lights off dryback)
Also I use cyco coco Pearl.
 
jguit

jguit

Supporter
906
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I guess the part i'm not understanding, is why the 8 second shots to reach field capacity before the drybacks? I'd imagine that's no different than one larger shot.

The floraflex graphic is saying something entirely different from what you are explaining for generative steering. Unless i'm reading it wrong, they're saying to reach field capacity/drain with shots over the course of several hours then one large dryback overnight.

I'm sorry if i'm missing something silly. Crop steering is something i wanted to try.

Flora steer
 
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jguit

jguit

Supporter
906
143
This is the version of crop steering (rockwool) i'm more accustomed to reading about. The principals might work in coco but you curiously dont hear of many people doing it (CEC?). I'd probably just give it a go in rockwool at that point. haha

 
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E

Enzo

17
3
I guess the part i'm not understanding, is why the 8 second shots to reach field capacity before the drybacks? I'd imagine that's no different than one larger shot.

The floraflex graphic is saying something entirely different from what you are explaining for generative steering. Unless i'm reading it wrong, they're saying to reach field capacity/drain with shots over the course of several hours then one large dryback overnight.

I'm sorry if i'm missing something silly. Crop steering is something i wanted to try.

View attachment 1227208
The general point is the same but I use the floraflex strategy without runoff. They would like you to irrigate until you get runoff in order to Bring your EC value down every light cycle. This can be wasteful if you’re not on your shit and can be avoided if you are. Since I am watering just to get my water content back to field capacity with no runoff I cannot allow my EC values to Spike is high. This allows you to maintain the EC without getting the fluctuation that you’ll get with a floraflex irrigation strategy.
I believe there is a thread on here or on the roll it up forum call Coco trees where one of the members “DJM” runs this strategy. He irrigates very tiny amounts up to 20 times a day getting zero runoff and maintaining an EC within .1 of his input and does this with monster trees. Like bigger than 6 ft. That’s where I got the no runoff strategy. And aroya have training on this as well.
 
Anthem

Anthem

3,323
263
This is the version of crop steering (rockwool) i'm more accustomed to reading about. The principals might work in coco but you curiously dont hear of many people doing it (CEC?). I'd probably just give it a go in rockwool at that point. haha

The Aroya system is pretty cutting edge.
@Enzo you are using their sensors and the floraflex crop steering software?
I know Aroya offers a complete system but the cost is thru the roof for a craft farmer
 
E

Enzo

17
3
I guess the part i'm not understanding, is why the 8 second shots to reach field capacity before the drybacks? I'd imagine that's no different than one larger shot.

The floraflex graphic is saying something entirely different from what you are explaining for generative steering. Unless i'm reading it wrong, they're saying to reach field capacity/drain with shots over the course of several hours then one large dryback overnight.

I'm sorry if i'm missing something silly. Crop steering is something i wanted to try.

View attachment 1227208
My bad. Floraflex has this labeled vegetative. But my dry backs are greater.
 
9CDA9805 358B 4BDB 87DF 747C1B55790D
E

Enzo

17
3
The Aroya system is pretty cutting edge.
@Enzo you are using their sensors and the floraflex crop steering software?
I know Aroya offers a complete system but the cost is thru the roof for a craft farmerjust sensors.
The Aroya system is pretty cutting edge.
@Enzo you are using their sensors and the floraflex crop steering software?
I know Aroya offers a complete system but the cost is thru the roof for a craft farmer
Just the sensor. Not the automation software.
 

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