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EC/PPM guidelines for coco?

The blue lab ec/ppm meter is amazing it is well worth the money!!
Yeah you don't see complaints about BlueLab. Does anyone know if the TDS (EC x 500) setting on Bluelab meters uses the NaCl conversion curve?

The new Nutradip Growboss has NaCl, 442 and EC. There are lots of complaints about it's predecessor the Tri Meter, having interference problems. Also it clearly looks Chinese made. I've emailed Future Harvest to ask if this model has better shielding than the Tri Meter, awaiting reply.

As for pens, the HM Digital COM100 has all the conversion curves, and .01 accuracy. I don't think they're as well built as Hanna or Bluelab though, some reports of them failing quickly or being DOA, giving 0.00 readings, etc...

I'm also looking at the MyronL Ultrapen PT1. That is the cheapest price I've found. It has .01 accuracy, NaCl, EC, and 442 (which MyronL company invented). It reads salinity too. They also have a PT2 pH pen. These are USA made. My only concerns are the tiny readout, and that I might lose them. MyronL makes some expensive handheld and heavy duty industrial meters that look really nice, for those with money to spend.

I went on a meter tangent.
 
For the record, Bluelab TDS 500 does use the NaCl conversion curve. Future Harvest hasn't replied to my email about the Growboss.
Not sure if I want to save up for the Bluelab Guardian Connect, or just get the regular Guardian.
I don't like how they charge more for the Connect, but you still have to buy the USB stick separately.
 

Phases

Member
I am wondering if anyone who uses 6/9 ratio with GH micro/bloom can tell me what ec you get - I have .2ec tap water and when I mix up 6/9 I get 1.2 -1.3ec

I have heard others that get way higher ec then that. I just want to make sure my meter isn't messed up. The bluelab doesn't need to be calibrated right? I should look into that.
 

Phases

Member
The bluelab guardian connect looks pretty sweet. That would be awesome to log all the readings automatically and organize it using the blue lab software.

So many amazing products out for growing these days, I love it. I always have my eye on something new - next I want to get a timer that does seconds so I can set up drip system and be able to do multiple feeds with shorter feed times. Gotta love the coco!
 

stoned40yrs

Ripped since 1965
Veteran
I am wondering if anyone who uses 6/9 ratio with GH micro/bloom can tell me what ec you get - I have .2ec tap water and when I mix up 6/9 I get 1.2 -1.3ec

I have heard others that get way higher ec then that. I just want to make sure my meter isn't messed up. The bluelab doesn't need to be calibrated right? I should look into that.

I have a new bullet proof bluelab truncheon. My well water is around .3 ec and I get 1.2-1.3 ec with full strength 6/9. Don't worry about what other people get, yours is reading fine.
 

CoCoSativas

Active member
I know I've seen posts with general guidelines for feeding strength based on age in coco but I can't find it now. Can anyone point me in the right direction or repost the info? Yes, I know it's all strain and plant dependent but with being new to coco a general idea of where to start is what I need. Thanks

My starting tap water is 200 ppm (.4 ec)

In veg my final ec is 600 is

Most of my bloom 650 to 750 depending if I use pk 13 14

I use canna nutrients and grow sativas. A little goes a long way. I could probably use less with some.

I'm experimenting running the same mix start to finish with my canna ab set except adding pk 13 14 for part of flower
 

CoCoSativas

Active member
I have a new bullet proof bluelab truncheon. My well water is around .3 ec and I get 1.2-1.3 ec with full strength 6/9. Don't worry about what other people get, yours is reading fine.

I hear the truncheon is dope I have a Hanna combo pen the black o e... I like it works good.
 
My friend has the Truncheon, it works great.

For a 24/7 monitor, I just scored this used Myron L EC meter on ebay for cheap. It was just the meter. Had to buy a sensor, different range module chip (0-2000 µS), and cal solution. The whole thing is gonna set me back $420.

The sensor was the most expensive part by far ($233). It has a threaded fitting for immersion if I want to drill a hole in my reservoir. Might as well.

They've got another box this connects to, which allows it to read 3 different EC probes at the turn of a dial. Now I just need to make room for another rez... and some more drip trays.

 

matt11

Member
ec guideline

ec guideline

When I first started cultivating in coco I followed these guidelines for my ec, . Some Specific strains get fed a little more, but its a really good baseline guideline, and I still abide by it, generally, to this day.
Props to snow crash for posit g it awhile back.

Seedling Stage:
400 to 500 uS/cm
Focus on Cal-Mag, and run a balanced system. You don't want to push just Nitrogen, Phosphorus will help with root development and potassium will balance out the cation exchange. Aim for a 1-1-1 kind of system, the most prevalent element in use at this time should be Calcium

Vegetative Stage:
Week 1: 600uS/cm Maintain the balanced ratio 1-1-1
Week 2: 800uS/cm Increase Nitrogen levels. 2-1-1
Week 3: 1000uS/cm Increase Nitrogen levels, watch for Magnesium shortages. 3-1-1
Week 4: 1200uS/cm Increase Potassium levels 3-1-2

Transition to flowering:
For 2 waterings you'll want to use a more balanced nutrient system and to decrease your Calcium supplementation considerably. If you were using something like GH Micro, or Botanicare Cal-Mag plus at 5ml in veg, this would be the time to cut it back to more like 2ml. Often, after 3-4 weeks in the media the coco achieves the element buffer (or bank) and pushing the continuously high levels of calcium will interrupt the exchange of Magnesium and Potassium during early flowering.

Flowering Stage:
Stretch wk1: 1200uS/cm Maintain vegetative NPK, decreasing Ca, increasing Su+Mag
Stretch wk2: 1200uS/cm Decrease N, increase PK slightly, close to a 3-2-3.
Flower wk3: 1350uS/cm Decrease N more, closer to 2-2-3
Flower wk4: 1450uS/cm Increase Mag and potassium.
Flower wk5: 1600uS/cm Begin PK boosting. 1-2-3
Swell wk6: 1800uS/cm Phosphorus push 1-5-4
Swell wk7: 1600uS/cm cont'd phosphorus push 1-6-4
Ripen wk8: 1400uS/cm very low nitrogen and calcium. 100us/CM extra Epsom Salt and increased K. 1-2-3 again.
Ripen wk9: <500uS/cm flushing. I like to use Fulvic acid for a few days.


https://www.icmag.com/ic/showthread.php?t=211179
 

srich250

Member
such good coco EC feeding info. ! This site is the bomb because of all the good peeps that contribute!!!

PLEASE HELP:)!!!!

I just got into week 4 flowering bomb girls that were probabky the best I've ever done.until 5 days ago when they all looked like they were dying. The leaves started turning grey with a day or so. No too burn at all as off day 25. They are about 30-36" tall and about 12-16" diameter.

Two weeks before this I sprayed with "green cleaner" as a preventative to spider mites and powdery mildew. Then 1 week before this I sprayed with mighty wash. Lights off or just before they went off.

I can't figure out what is killing them. The sprays or my feeding.

I've grown 1000's of girls and I've never killed them all like this except burning them to death in coco when I tried it my first two times. Over feeding and letting it go dry between watering. Burned every 4-5' tall thick plant to a crisp before I could flush and try saving them. I tried but they never recovered.


So back to solving and hopefully saving these ladies now in week 4:-(

I'm using advanced nutrients grand master full line. They say to feed max every feeding with 15-20% runoff. But that's an EC2.5/3.0 or Hanna ppm 1250/1500. Depending on what week you are following the schedule.

Here's my setup
Environment
Temp 75-81
RH 45-65%
Co2 800-1200ppm
Lights are mixed
- Fluence spydrX 1200, 630w CMH DE, and a 1000w DE ePapillion
1gal hard pots canna coco coir DTW
advanced nutrients grand master line
Filtered water is EC 0.3
Oxygen stone in nutrient "brain bucket" for mixing


I have usually been feeding about 4-8oz per plant 1-3x per day.
I have been checking runoff and even if I feed at 2.5 or 3.0 the runoff even while they are dying is EC1.6-3.0 max. So I'm doubting if it's my feeding even though I don't know why they say to feed max nutes per their schedule with runoff every time. I have called them many times and they all say the same thing. So I only do a max feed once per week and then it's been more like 1.6-2.2EC.

RUNOFF ALWAYS GOES DOWN AND so I can't figure out how I killed them all.

I know this is a tough one to figure out. I will post pics also.

The one thing to know is that the plants that were in the shadows with low light are almost perfect. Not burned at all. ??????????? Weird!!!!

Please help:) I cherish this site and so many experts out there. I'm new to coco except for my two failed runs a couple hrs ago which is why it took me this long to try it again.
 

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srich250

Member
I'm hoping these links work: Here are the 5 pics associated with my post above. How do you guys upload high quality images ? Do you save them to your albums first, the insert? Or is there a better way to get high quality from my iPhone to here? Thank you


 

MoPho

Member
such good coco EC feeding info. ! This site is the bomb because of all the good peeps that contribute!!!

PLEASE HELP:)!!!!

I just got into week 4 flowering bomb girls that were probabky the best I've ever done.until 5 days ago when they all looked like they were dying. The leaves started turning grey with a day or so. No too burn at all as off day 25. They are about 30-36" tall and about 12-16" diameter.

Two weeks before this I sprayed with "green cleaner" as a preventative to spider mites and powdery mildew. Then 1 week before this I sprayed with mighty wash. Lights off or just before they went off.

I can't figure out what is killing them. The sprays or my feeding.

I've grown 1000's of girls and I've never killed them all like this except burning them to death in coco when I tried it my first two times. Over feeding and letting it go dry between watering. Burned every 4-5' tall thick plant to a crisp before I could flush and try saving them. I tried but they never recovered.


So back to solving and hopefully saving these ladies now in week 4:-(

I'm using advanced nutrients grand master full line. They say to feed max every feeding with 15-20% runoff. But that's an EC2.5/3.0 or Hanna ppm 1250/1500. Depending on what week you are following the schedule.

Here's my setup
Environment
Temp 75-81
RH 45-65%
Co2 800-1200ppm
Lights are mixed
- Fluence spydrX 1200, 630w CMH DE, and a 1000w DE ePapillion
1gal hard pots canna coco coir DTW
advanced nutrients grand master line
Filtered water is EC 0.3
Oxygen stone in nutrient "brain bucket" for mixing


I have usually been feeding about 4-8oz per plant 1-3x per day.
I have been checking runoff and even if I feed at 2.5 or 3.0 the runoff even while they are dying is EC1.6-3.0 max. So I'm doubting if it's my feeding even though I don't know why they say to feed max nutes per their schedule with runoff every time. I have called them many times and they all say the same thing. So I only do a max feed once per week and then it's been more like 1.6-2.2EC.

RUNOFF ALWAYS GOES DOWN AND so I can't figure out how I killed them all.

I know this is a tough one to figure out. I will post pics also.

The one thing to know is that the plants that were in the shadows with low light are almost perfect. Not burned at all. ??????????? Weird!!!!

Please help:) I cherish this site and so many experts out there. I'm new to coco except for my two failed runs a couple hrs ago which is why it took me this long to try it again.


Sorry to be the bearer of bad news. IME your plants are dying due to phytotoxicity. I've used Mighty Wash before w/o any bad effects, so my guess would be the "green cleaner".

When it happened to me nothing I did helped the plants. Most of them died and the ones that survived barely yielded anything worthwhile.

I know you don't want to hear this, but I think scrapping them and starting over is the best bet. However if you really must, you can try cutting away all the dead or dying materials and let the rest continue. I did try that myself and eventually even the parts that "were looking" healthy ended up dying anyways.

Sorry....I know it sucks.
 

stoned40yrs

Ripped since 1965
Veteran
It's not the Green Cleaner, it's that fucking Mighty Wash. I fucked up a bunch of plants in veg with that crap and that's exactly what the leaves looked like. I sprayed, turned off lights and next morning when I turned the lights on they all looked like yours. 100% guarantee that Mighty Wash did that to you and me!
 

MoPho

Member
Well one or the other. IMO at this point he is better off trashing those plants and starting over instead of wasting more time and end up with nothing.
 

srich250

Member
It's not the Green Cleaner, it's that fucking Mighty Wash. I fucked up a bunch of plants in veg with that crap and that's exactly what the leaves looked like. I sprayed, turned off lights and next morning when I turned the lights on they all looked like yours. 100% guarantee that Mighty Wash did that to you and me!


And to MOPHO!

Thx to you both.

Sorry to be the bearer of bad news. IME your plants are dying due to phytotoxicity. I've used Mighty Wash before w/o any bad effects, so my guess would be the "green cleaner".

When it happened to me nothing I did helped the plants. Most of them died and the ones that survived barely yielded anything worthwhile.

I know you don't want to hear this, but I think scrapping them and starting over is the best bet. However if you really must, you can try cutting away all the dead or dying materials and let the rest continue. I did try that myself and eventually even the parts that "were looking" healthy ended up dying anyways.

Sorry....I know it sucks.



---- plus "stoned40yrs---


Man you guys thx for the feedback. This is the worse feeling ever. I've killed so many ladies trying coco twice on too big of runs and this was going so well I could see why so many of you (especially mr stoned40yrs, do coco with such success.!!! They were amazing. So healthy my friends and partner she was blown away compare to the 1000's grown before.

Is there anyway that it could be nutrient burn since like an idiot I pushed the limits again with feeding?????

One thing I figured out at 10 last night is that I bought a new brand of advanced nutrients PH DOWN instead of my old brand not sure of.

I started to flush them again with 50gal EC1.0(500ppm hanna), but the ph was like 8.6. So I had to add like 12oz just to get it to go down to 6.5. So I started to flush about 30min later and then I decided to recheck the EC which I never do once it's spot on. I just adjust ph after mixing nutes carefully and slowly and then ph for about 5-15 min then water.

But I shit a fucking brick. The EC went from 1.0 to 3.6. I grabbed my girl and showed her while we were working on getting ready for the flush. She shit a brick too. How the hell is it possible for the EC to go up 350%??????

So I grabbed my newer high end Hanna probe EC meter and it said 3.5 and the blue labs said 3.6. Put a new battery in the blue labs and same 3.6.

I know npk phosphorous raises EC but this is crazy.

All nite companies say prep water,
Add nutes and properly adjust EC. Then ph if need be. Then water. Why don't they say in. If bold letter , this raises the EC , dbl check EC after adding ph down????????

So it gets worse. I took EC 0.8 of 16oz nutes, added a couple ounces of advance nutrients ph down and it went to EC 13.2 in less than a minute !!!!!!!!!!!!!!!! I only did it as a test just to troubleshoot what the hell I did wrong to kill every plant ?????????????

The only odd thing is out of 75 dead ones, there is one that is absolutely perfect.

Stoned40yrs, I was with you on the might wash. But then we were like how did this girl not get hurt and no tip burn at all either!!! Well we did a runoff and a soil meter tip test for EC on about 9 plants. 8 of the worse and this one golden girl. It had a runoff of 2.0 and EC tip insert Hanna tool was 1.6. It's always lower because less conductivity in the soil compare to straight water runoff. All others were EC 3.5-7🤕

And of course they all got Saturday's with a professional powered sprayer that saturates every mm of every leaf so the golden girl was also saturated with both the wash and green cleaner.

So is it more possible now that since for about 7-10 days I had an EC of 2.0-3.0 it then I PH it from about 8.5 down to 6.5 for this watering period that I killed them that quickly ???????????

I truly appreciate your thoughts and suggestions and help.

I know I have to cut my losses and thank God that Cannabis grows so quickly so my veg plants can get ramped up quickly now. But I still lost the best crop I've had in my life so far. Plus 28 new genetics which was the first time I've ever spent so many months spending a lot of money on seeds and phenotypimg etc etc 😂
Thankfully I saved a small mother of each just in case some
Of these Phoenos were bomb!!!!!!


Uhgggggggggg!!!!! I'm so bummed and financially this is going to crush me:-(! For a while!!!!!!
 

Weeded1s

Member
Yo ..since your in the coco section i assume your in coco.
With that said ... 6.5 ph in coco is never ever ok!
Lastly i hope your doing slurry tests and not just str8 runoff test. :)
 

MoPho

Member
srich250

This is from my experience, when I get nute burns, I usually see it starting from the bottom up. Almost all the leaves look healthy except for a few bottom leaves first turning a deep yellow (light yellow is more likely a nute def) then those leaves would crisp up (slight brownish color). If the problem is not addresses then it progresses through the entire plant.

With that said, your situation "might" be overfeeding, but I highly doubt it. IME leaves turning gray is usually a sign of phytotoxicity. Which I think is the case because you sprayed them with Mighty Wash and Green Cleaner (<---what is that by the way?).

Now those EC and ph numbers that you posted, are those readings from your res or your run off. The reason I ask is because if there are bacteria in your root zone that can lead to crazy readings (especially ph), too. Which can be another reason why your plants are dying. I've also experienced this myself, where my roots were dying and the plants looked completely healthy. Then within a few days, the leaves turned gray etcetera. If you are scrapping this grow, a very easy way to tell is by yanking the plant and if it easily breaks away from the roots then you'll know that you this was/is the cause of your plants dying.
 

MoPho

Member
"I'm using advanced nutrients grand master full line. They say to feed max every feeding with 15-20% runoff. But that's an EC2.5/3.0 or Hanna ppm 1250/1500. Depending on what week you are following the schedule."

That sounds high no matter what week you are in. If you are feeding with run off 600-700 ppm is plenty. Saves on nutes too :). If you haven't, I suggest you read
https://www.icmag.com/ic/showthread.php?threadid=300255
Read through the entire thread, yes it is quite a bit, but the first few pages will give you a great head start. Or you can filter the posts made by DJM and go through the entire thread when you can.

Also if you don't mind me saying...I would skip all the brand that requires a ton of different bottles. Go with the K.I.S.S method. If you go that route and get everything dialed and have a good grasp of what to expect from your garden that's when you can tweak things here and there.

Just my $.02 hope that helps.
 

stoned40yrs

Ripped since 1965
Veteran
Man you fucked them up with that advanced nutrients ph down. I use that potent shit also. Not only did it jack the hell out of your ec it also probably made your ph in reality about 0.0 damn, that's what 12 oz of that shit would do in a 50 gal tank. To take that 50 gal of 8.6 ph down to 6.2 would be ml not ozs. At the most it would only take between 15-20 ml. Around 1/2 oz or so. It's the most potent ph down on the market. Battery acid. I spilled a couple oz on my carpet. It started smoking and bubbling and ate through the carpet and the pad and was working on going through the wood like blood from the Alien monster. I dumped a box of baking soda on it to get it to stop.:biggrin:
Oh ya, I had a couple plants that didn't get fucked up by the mighty wash. It's selective on which ones it fucks up.
 
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