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EC/PPM guidelines for coco?

gardenbug

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
 

gardenbug

Member
A good thread on feeding is stickied above in this coco forum. "HEad goes coco" check it out

I've read the entire thing before, it may be where I saw the chart I'm looking for but after a few days of searching the forums I still can't find it.

I'm looking for something like:
Week 1 xxx EC
Week 2 xxx EC
etc....
 
Hey gardenbug,

Generally the nutrient manufacturer supplies feed charts which can be a decent 'guide' - many growers may disagree but it's a good starting point imo!

I would presume you have already checked out the website of the nutes you are using to see if they have a coco feed chart (if you are using coco specific nutes). Coco specific nute manufacturers 'house & garden' & 'nutrifield' websites both have good feed charts (if you just ignore all the additives they list for the base nutrient guide) - though I think once you head off in the direction of non-coco specific nutes whereby you don't know the effectiveness of them that's where experienced advice is useful...

If i remember correctly, when I used GH nutes in coco I just followed the Lucas formula and it worked, I just did a google search of the lucas formula and there is heaps of info out there, check out --> 'What's the idiots guide to the Lucas forumla - TCHframer' - scroll down and a member of this forum has put it in a neat table :D

Hope this helps! TTK
 

Snoopster

Active member
Veteran
What kind of nutes?

I use GH nutes and the Rezipe. I don't worry about ppm, it will be about 850 with the 6 to 9 ratio. After mixing nutes, the water has been 5.85 ph for me :jump:

I use 50/50 R/O water and tap water.

If you are not using GH nutes, you can figure out the ratios based on what is in the nutes.


https://www.icmag.com/ic/showthread.php?t=81674

==The Recipe==


(All Products are GenHydro,pH at 5.5 pH)
(All measurements are per gal.)
6ml flora micro
9ml flora bloom
Kool-Bloom POWDER

VEGETATIVE STAGE AT 24 HRS. LIGHT ON
(18/6,optional)

Veg,Feed:

6ml flora micro
9ml flora bloom

Use the above 1/2-strength on seedlings and clones to 10" tall,then feed full-strength>on.




Based on 63 day 12/12 Flower Cycle:

Day 1-14
6ml micro
9ml bloom

Day 15-21
6ml micro
9ml bloom
1 tsp./Gal. Kool-Bloom POWDER (ONE FEED,DAY 15!)

Day 22-28
6ml micro
9ml Bloom

Day 29-35
9ml Bloom
1 tsp./gal. Kool-Bloom POWDER (ONE FEED,DAY 29!)

Day 36-52
9 ml Bloom
(AND ON DAY 36,a 1 tsp./gal Kool-Bloom POWDER Slam!!)

Day 52-63 (Flush)
5.5-6.0 pH h20 at 50 ppm
 
Last edited:

HawaiinRock

New member
when i use the lucas formula in VEG it sucks to be honest. 6/9 and my plants are not half as dark green as they should be, and my tops are slightly yellow out the growing shoots. for the last week i have since changed, and have tried 2 formula's. i have 3 4x4 trays, under 3 1000's. environment is absolutely perfect. 80's. upper 40's -50% humidity, lights on movers, RO water, the works. plenty of fresh air changes too. 18k BTU Mini split AC to top it all off. anyhow, 3 trays, 3 different fert experiments. lucas tray just not cutting it. the other tray is much better, it's lucas at 2x strength. the 3rd tray is best. 20ml micro, 14 bloom, and 2 grow. got it here. http://www.angelfire.com/cantina/fourtwenty/articles/profiles.htm

within 2 days my plants turned darker green, and no more yellowing or lime green tops. my EC is between 3.0 and 3.5. the lucas formula was very low, less than 2.0 EC if I'm not mistaken. my plants just don't like lucas formula, but i also have 3 1000's that are air cooled from another source and have an AC. so my plants are SCREAMING. praying so tall that the leaves are standing higher than ever.

i also have to run about 15 ml of Flora nova bloom to keep up. running a side experiment on a few plants. 3 plants in each tray that are 5 ml,, 10 ml , and 15 ml. the 15 ml have been getting noticably better all week.

the trick is to know how to maintain coco. keep it slightly moist, so it doesn't dry all the way. and remember, it's like a bunch of little sponge pieces. so you have to monitor your runoff all the time. oh. and when i swithced from a 5.8 ph to a 6.0, got way better. way better. you don't need runoff every time, i do it every other time. saves time, money, water, nutes, everything. just understand why you're doing things instead of what you're doing. always use a .5 conversion, no matter what your meter says. use EC, calibrate often, and take it in half at that will be your ppms. I have a hanna 9813-6, which uses a .7 conversion, so when i was using ppm, it was hurting me. stay with EC and take half of it as your ppm. and if you're using 1000's, go right to 1500 ppm. but you have to make sure your environment is spot on. i struggled all month with the lucas formula. it's misleading because 6/9 the ratio, not the concentration. 3.0 EC minimum for me.
 

Snow Crash

Active member
Veteran
Hey Garden Bug. I have what you're looking for.

I don't know why, but for whatever reason people just don't keep track of this stuff (or they refuse to share it). I asked for similar information a time ago and got "run out of town."

I speak in uS/cm. It is a more accurate representation of EC, and if you cut the value in half that would be the Hanna ppm measurement. Also, for beginners in coco, I think that the Botanicare CNS 17 coco/soil system of Grow/Bloom/Ripe is damn near perfect. It's about $10 a quart, $25 a gallon, it has everything you'll need, and it works. Their instructions are a little high ml/gallon wise, but you can always cut them back to about 75% suggested strength and go from there. IMO, there is not an easier and less expensive complete system than CNS 17 Coco/Soil. The addition of a Potassium Silicate (like Pro-Tekt) can be useful as a pH up for this usually acidic system, rather than using GH Potassium Bicarbonate pH+.

For the record, my tap water comes in around 100uS/cm (about 50ppm) so it is pretty clean to begin with. For most growers, if you do not have access to clean water (like if you live in a major metropolitan area with water treatment) then I recommend running Reverse Osmosis filtered water to ensure contaminants (like sodium) are not unbalancing your system.

These nutrient levels are what I consider to be average ballpark. Every strain, and phenotype, is going to have its own "perfect level." These suggestions should be fine for most strains, but you might be able to push more nutrients during weeks 3 and 4 of veg and 4 and 5 of flowering than I suggest. You'll have to determine that as a gardener when you can see what the plants will actually require.

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.

Some other things that might help out. I don't like to grow in large containers of coco, I just think it is unnecessary. 8L of coco is plenty. Also, I prefer to amend my coco with aeration material like perlite and GrowStones. I think Roots Organics Coco mix is a fantastic media that you can use much less nutrients on (until the 4th week in the media) and I like to mix a little Botanicare CocoGro in with their mixture because it is a little heavy in perlite when unamended.

When daily waterings start (usually in the 3rd week of flowering for me, but it will vary given planter size and transplant date, etc) I begin to offset my feedings with 1/2 strength waterings. Every other, or sometimes every 2 full strength feedings I follow up with a lower strength watering at a balanced ratio. This will keep buildup a non-issue.

Also, when feeding at higher strength, and especially around the transition phase to flowering, I find that it is VERY important that I maintain at the minimum 33% run off (3L in, 1L out). Measure your runoff EC to determine if you are washing out a lot of buildup. If I use a 1000uS/cm solution and if I get anything more than 1300uS/cm in the runoff then I know that the media is a little over-saturated and this is washing out. In this case I simply continue to rinse the media with the 1000uS/cm solution until the runoff measures within the range I am looking for. Usually, a 1:1 runoff ratio (4L in, 2L out) is all it takes to keep any buildup completely out of the equation.

Here's a nutrient calculator I have put together using a spreadsheet (I made it in openoffice and converted to .xls)

http://www.megaupload.com/?d=EGSYJSW8

Just enter the required information and you are on your way. You will want to measure your ppm levels compared to the predictions and compensate for deviances. Liquid Karma tests about 9x higher than predicted, while Hydroplex tests about 90% of predicted. This calculator requires personalization, but it is setup to predict up to 10 nutrients at a time in a solution. I have mine dialed perfectly when running:
Canna Coco A
Canna Coco B
Cal-Mag Plus
Liquid Karma
Pro-Tekt
CNS 17 Ripe
Hydroplex
Big Bud
Nirvana
Snow Storm Ultra
Bud Candy

This is where these levels, my 2 years of experience, and this calculator have taken me (40 days from 12/12, sorry about the white balance, not burned just glare)

img6816.jpg
 

gardenbug

Member
Thanks, just wanted to make sure I was feeding about right. I'm at 3 weeks veg under about 200 watts t5's and cfl's.
Botanicare cocogro didn't rinse it just fed with lots of waste the first few times. Drip fed once daily now. Tap water at 40ppm.
House and garden coco formula
1ml/gal calmag
1ml/gal silica
1ml gal roots excel
.5ml/gal drip clean

500 ppm at .5 conversion and 5.8 PH.
They seem to like it so far. Still having some calcium deficiency but I was at 300ppm before, 500 seems to be helping.

Just wanted to add the root growth in coco is amazing. Almost as fast as dwc. I've got them in 1 gals and going to move to 3 gals, then probably to 5 gals.
 
G

Guest 18340

when i use the lucas formula in VEG it sucks to be honest. 6/9 and my plants are not half as dark green as they should be, and my tops are slightly yellow out the growing shoots. for the last week i have since changed, and have tried 2 formula's. i have 3 4x4 trays, under 3 1000's. environment is absolutely perfect. 80's. upper 40's -50% humidity, lights on movers, RO water, the works. plenty of fresh air changes too. 18k BTU Mini split AC to top it all off. anyhow, 3 trays, 3 different fert experiments. lucas tray just not cutting it. the other tray is much better, it's lucas at 2x strength. the 3rd tray is best. 20ml micro, 14 bloom, and 2 grow. got it here. http://www.angelfire.com/cantina/fourtwenty/articles/profiles.htm

within 2 days my plants turned darker green, and no more yellowing or lime green tops. my EC is between 3.0 and 3.5. the lucas formula was very low, less than 2.0 EC if I'm not mistaken. my plants just don't like lucas formula, but i also have 3 1000's that are air cooled from another source and have an AC. so my plants are SCREAMING. praying so tall that the leaves are standing higher than ever.

i also have to run about 15 ml of Flora nova bloom to keep up. running a side experiment on a few plants. 3 plants in each tray that are 5 ml,, 10 ml , and 15 ml. the 15 ml have been getting noticably better all week.

the trick is to know how to maintain coco. keep it slightly moist, so it doesn't dry all the way. and remember, it's like a bunch of little sponge pieces. so you have to monitor your runoff all the time. oh. and when i swithced from a 5.8 ph to a 6.0, got way better. way better. you don't need runoff every time, i do it every other time. saves time, money, water, nutes, everything. just understand why you're doing things instead of what you're doing. always use a .5 conversion, no matter what your meter says. use EC, calibrate often, and take it in half at that will be your ppms. I have a hanna 9813-6, which uses a .7 conversion, so when i was using ppm, it was hurting me. stay with EC and take half of it as your ppm. and if you're using 1000's, go right to 1500 ppm. but you have to make sure your environment is spot on. i struggled all month with the lucas formula. it's misleading because 6/9 the ratio, not the concentration. 3.0 EC minimum for me.

Lucas formula far from sucks in veg. It works absolutely perfect, in fact. I can guarantee the problems you had were operator error, not the fault of the Lucas formula.
Here's a shot of a (Mr.Nice) Shit plant in veg. Fed lucas formula (8/16) and tap water...



I highly recommend the Lucas formula for beginners. It's simple, cheap and proven.
PS. Lucas formula is 8/16, not 6/9...
 
Last edited:

socket

New member
Cannastats makes a poignant observation that there is a lot of variation in EC numbers between growers. His take away from that was Cannabis does fine with a wide range nutrient profiles. This is very true to some extent. But, in my opinion, two major factors influence whats the "correct" number. The #1 most important is lighting (PAR output) and strain specific requirements.

We all know some strains are heavy feeders while others tend to not be. We also know how much nutrient is needed depends on how fast and big a plant is going to grow. Which is directly influenced by your lighting. I think if we assume everyone is growing under 600 watt HPS the 1.8-2.2 mS/cm mark is about right. But that number is not right for someone growing under 400 watts of fluros or 1000 watt HPS.

As for pH in coco I believe it's important to drift. Also depending on how dry you let your coco get substrate pH will drop dramatically as the media dries (something to think about). But I've found drifting between 5.2 and 6.0 (i tend to max out at 5.8 actually) is a good policy. It helps uptake on on the elements that might be a bit scarce on either end of the spectrum.
 

jackiee

Member
hi, i think socket was spot on with his analysis, my ph is 5.8 or as close as i can get,my ec starts in veg 1.0 and rises to 1.6 in flower with a little drift now and again. stay lucky
 
D

DHF

Usedta jack ppm`s back in my krusty bucket days with big plants , but we flushed residual salts every 5-7 days......

When I went to smaller plants with increased numbers I found less was more , and never ran over 750 ppm`s for well over a decade with dialed results.....

Granted , some strains/varieties will take more elevated ppm`s , but to what end.....I mean......especially with coco and it`s inate ability to hold onto nutes before releasing em to the plants , folks should think about gettin rid of all residual salt buildup in late flower so as to allow the plants to cannabilize themselves till end of cycle and eat all residual salt that`s left after dwindling ppm`s as low as possible in a dialed setup before harvey/chop IME.......

I`ve never run anything but GH 3 part , but with coco I ran 10/15 micro and bloom with 5 ml cal/mag , 5 ml silicablast , 5 ml sm-90 , and 1 ml roots excellurator , with 15-20% runoff DTW......

The only thing I`d do different today would be to implement Dripclean @ 1ml per gal and no runoff to save all the wasted juice I pissed away over several yrs......

6.0 was always my target zone for ph , but set it in the low-mid 5`s with my feed and let the rootzones adjust all the way up to 6.2-3 as they were fed till rez swapout.....As plants eat , ppm`s drop and ph rises gradually.....in a dialed setup....that way macro`s and micro`s are absorbed properly at different ph levels till it rises to adjustment level and starts all over again after new rez mixtures happen...

Less is more....the more ppm`s/ec you can leach out of coco rootmasses and plant matter before harvey , the better your end product/results will be....guaranteed....

Peace....DHF.....:ying:......
 

socket

New member
How much you flush tends to be decided on how much runoff you have during feedings.

Neat way to avoid having to "flush" at all.

If you follow the Feed,Feed,Water rotation as lots of people do. Personally I don't because I my feedings generally acheive a large amount of runoff.

But if your not running off much or at all during your feeding you can just make the "water" part of your feed,feed,water rotation a very low EC feed instead and shoot for 50-60% runoff. Something like 200-300 mS/cm works really well to flush excess salts from the medium.

Or you can just shoot for 20-30% runoff during feedings and not worry about flushing at unless runoff indicates buildup. I only use flushing solution during my final flush normally. Unless I'm too aggressive with my feeding schedule and buildup occurs.

Coco for me (at least with the nutrients I use) has been very forgiving regarding salt build up. But I'm also not overly aggressive with my feeding regimen.
 

Snoopster

Active member
Veteran
PS. Lucas formula is 8/16, not 6/9...


The 6/9 is the adjusted Lucas formula for hand watered coco, Rez came up with it, "The Rezipe."

The Lucas Formula site says to adjust for coco and links He3d's thread, which suggests using 6/9.
 

Critter

Think for yourself, question authority
ICMag Donor
Veteran
Im hoping DHF or someone can help me.

I have a bunch of seedlings I started in coco still in solo cups. They are about 3 weeks old but are having problems,

They are small,Geen/lime green, yellow on the bottoms.

I see a little tip burn/yellowing so i havnt pushed em above 400ppms. my water is around 80 ppm.

They dont look too bad just a little small. The soil ones i started way after are already over taking them in dark greeness and size of leaves (not number if nodes).

Any suggestions.

Feed is up to -2.5ml micro- 4ml bloom -1ml magi/cal -1ml dripclean -Greatwhite myco -1-2 drops superthive-

. ph 5.8. Watering every other day..

Im about to up to 3ml micro, 4.5ml bloom, 2ml magi/cal, 1ml dripclean

Was thinking about adding some Fox Farm bigbloom to the mix but Im scared to.
 
D

dramamine

Critter, those girls need to be fed more (base nutes). If you push it to somewhere around EC 1.2 you will see them green up in a hurry. Letting the coco dry a bit between waterings for seedlings can be helpful for root formation, but with hydro systems it deprives the medium (and the plant) of nutes. Anyway, in coco it only takes 2-3 days usually for decent roots to form, at which point the more frequent the waterings/feedings the better.

You might get other advice...there's lots of it out there. But much of it can almost make you afraid to feed/water for fear of salt buildups, overwatering, etc. I had this issue a couple times before realizing that I was simply underestimating what the small plants needed.

peace and good luck
 

gardenbug

Member
I'm up to 1.4 EC twice a day with 2ft tall plants in 3 gallons of coco. About 200 watts t5 light. I thought it would be too much but they seem to like it and I think the sour diesel wants more.
 

Critter

Think for yourself, question authority
ICMag Donor
Veteran
I upped their feed and they exploded and darkened right up. Ive only run clones in coco but now I know how to germ. Thanks for your help guys :wave:
 

jumanji2

Member
I don't want to start another thread so if someone can chime it would be cool..
I'm handwatering coco(hempys) 1st week of flower
nutes are
GH micro/bloom H3ads 6/9. Feed once a day, 20% runoff usually..
850ppm,PH 6 going in,
1200ppm runoff, PH is close to 5.(using drop kit)
Temps are 86/ 45% humidity.

Plant is healthy as can be from the looks. Does the high runoff indicate overfeeding??
I have had no problems at all which didn't make me think about it.

If coco holds nutes until the plant needs it I don't want to keep flushing,(I flush with low ppm solution) and deprive it especially in an important time. Or is this a non issue?
Some say the run-off isn't important cause that's coming out anyways. Or am I just over thinkn this lol thanks for your time.
 
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