Coco mag deficiency or lockout? Complete Guide sticky question list filled out

[richyrich]

HYDROPONICS/Aero Ponics/Coco/Soiless/

How long has this problem been going on? Started at 2 weeks veg after moved from 400w MH veg set up to 1000w HPS hortilux. Have not flipped to flower yet till resolved.
Are you growing in a PVC grow tent? (example: Hydrohut or any other non brand tents) No
What system are you running? (DWC? Ebb flow? Aero? Water Farm? Flood Tables? and so on...) Canna Coco feed to waste
What STRAIN are you growing? AK47
What was the establishing technique? (Were the seed or clone?) Clone
What is the age of your plants? 4-5 weeks veg
How long have they been in there mixture they are in now?(coco,soiless etc..) Straight Canna Coco; from clone to keg cups for 10 days (super healthy); then to 2g pots
How tall are the plants? 26"
What PHASE are the plants in? (seedling, vegetative or flower) are the plants in? Veg
What Technique are you using? Handwatering every other day at this point
What substrate/medium are you using?(Hydroton, RockWool etc.) Canna Coco
What is the Water temperature? 76F when hand watered
What color are your roots? White? Brown? Are your roots slimy? Healthy white
What Nutrient's are you using?(If growing soiless) Botanicare cal mag and flora nova
How much of each nutrient are you using with how much water? *Knowing the brand is very helpful* Using RO water; add .3ec of calmag and 1.2ec of flora nova bloom for a total 1.5 ec
How often are you feeding? (If using soiless) Every other day
How often are you giving nutrients? (If using soiless) Every other day
If flowering, when did you switch over to using Bloom nutrients?
What order are you mixing your nutrients? (example: veg nutes 1st, bloom 2nd ect) Calmag then Flora Nova then a little ph up; advance nutes brand
What is the TDS/EC/PPM you are using? 1.5ec total
What is the pH of the "Tank"? Feed at 6.0ph
Are you sure your calibration is correct on your equiptment? Calibrate religiously and double check with ph liquid dropper test
When was your last watering? N/A
What is your water temps? N/A
When was your last feeding change? (ie. grow-bloom-micro-additional) N/A
How often do you clean your system: example: Flush out water replace with clean water and nutrients? Don’t flush; feed continuously with 25% runoff each feed; feed to waste
What size bulb are you using? 1000w hps hortilux
What is the distance to the canopy? 30"
What is your RH Factor(Relative Humidity)? 55%; have dehumidifier
What is the canopy temperature? 75-78F; measured with infared thermometer
What is the Day/Night Temp? (Include flucutaion range) Day 81F / Night 73F
What is the current Air Flow? (cfm etc.) Lots of fans; sealed room running 1500ppm co2
Tell us about your ventilation, intake exhaust and when its running and not running ? N/A
Is the fan blowing directly at plants? Yes; very good air circulation
Is your water HARD or SOFT? RO water
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? RO Distilled? Mineral Water?
Are you using water from a water softener? No
Has plant been recently pruned, cloned off of or pinched No; not yet
Have any pest chemicals been used? If so, What and When? No
Are plant's infected with pest's No

Problem arose around 2 weeks after being moved under 1000w hps. Was feeding at 1.2ec at 5.8ph in the beginning; was going good. Growth accelerated and I inched the nutes up. Of that 1.2 ec in the beginning, I first added .3ec of calmag and the rest flora nova. Plants started to look like these pics of old fan leaves.

Old growth pics.


I first started adjusting the ph. I tried from a range of 5.6 to 6.1 over a course of 2 weeks with not much change. During the same time I began to notice nitrogen deficiency too, so I concluded that the plants were hungrier because of the wattage increase; especially, because the plants around the edges were more green. I began to inch the nutes up.

I have topped out because I am getting tip nute burn at 1.5ec. Leaves greened up more but cal mag problems still persist. I read heavily about using coco and flora nova with RO water. Consensus was split; some said no need for calmag and others said yes. I upped the calmag from .3ec to .5ec and not much changed. At the same time I upped the ph to 6.0-6.1 because many said it would allow mag uptake in coco. This was 4 days ago. My only other thought is lockout from too much calmag since flora nova has more than most other base nutes. Thinking of only feeding flora nova next feed. I would like your thoughts and help first.

Current pics; picked the worst looking ones; last pic is tip burn and some deficiency. Tip burn showed when I went from 1.4 to 1.5ec the last feed.


In the same room I have my moms. They were and continue to be fed from the same feed as these plants. They are medium sized mothers (nearly the same size) in the same pots and coco. They are fine; only difference is that they are under a 400w MH portioned off. I look at them as my control and I am stuck for a solution. I know I will get the response to drop the calmag, it's lockout, but if it does not work can you speculate on the next thought and solution, too. Thanks.

Here is a shot of the canopy from above.


Here is a healthy shot from a side corner. Next to the plant from pic above.


And next is s shot of a ebb n flow hydro I am running in the same room. Running .3 ec of calmag and a total of 1.4ec brought up by flora nova; ph drifting 5.8-6.1. I am perplexed because this is what I was running in the coco and these plants are just fine and in the same room.

 

[richyrich]

I was hoping for replies before todays feed, but it hasn't been that long. Fed today at 1.5ec at 5.9ph. RO water and straight flora nova. No calmag this time. About a 50% runoff. Will see what happens.

Advice still needed.

 

[10k]

imho, you'd have a lot more mag available if you were running in a chem hydro pH range of 5.1 to 5.9, targeting a 5.2 start and letting it drift through the range. Starting at 5.8 is about the weakest point for mag availability in chem hydro... however, no doubt several folks will say coco is more like soil on a pH chart...but, I beg to differ seriously

 

[BobbleheadJed]

Are you shaking the Floranova enough? And then shaking for ten more minutes after that? I just didn't have luck with Floranova. I think it puts out some really weird nute levels when it isn't mixed perfectly. Other than that maybe try lowering the nute level some. Coco needs lower nute levels than hydro in my experience because some of it remains in the coco. That might explain the difference between your hydro and coco plants. I might try the coco plants at 2/3 the nute level of the hydro.

 

[richyrich]

imho, you'd have a lot more mag available if you were running in a chem hydro pH range of 5.1 to 5.9, targeting a 5.2 start and letting it drift through the range. Starting at 5.8 is about the weakest point for mag availability in chem hydro... however, no doubt several folks will say coco is more like soil on a pH chart...but, I beg to differ seriously

I read a very recent response of yours to a person asking of a mag problem in coco too. I took your response from experience into serious consideration which is what you have posted here for me. It is the next thing I am going to do if dropping of the calmag doesn't do it. I was torn which way to go because so many people in the coco forum say mag becomes more available in coco at 6.0-6.1. So, this feed I just went neutral and fed in between the usual cited coco range of 5.8-6.0. I will adjust from here until it straightens out. Looks like I will be going down next. Thanks.

 

[richyrich]

Are you shaking the Floranova enough? And then shaking for ten more minutes after that? I just didn't have luck with Floranova. I think it puts out some really weird nute levels when it isn't mixed perfectly. Other than that maybe try lowering the nute level some. Coco needs lower nute levels than hydro in my experience because some of it remains in the coco. That might explain the difference between your hydro and coco plants. I might try the coco plants at 2/3 the nute level of the hydro.

I shake the heck out of the bottle. I started low and have worked my way up. Last round I had some fert burn and will not make the same mistake. That mistake made me learn that coco needs a lower ec as you have stated. Thank you.

 

[richyrich]

imho, you'd have a lot more mag available if you were running in a chem hydro pH range of 5.1 to 5.9, targeting a 5.2 start and letting it drift through the range. Starting at 5.8 is about the weakest point for mag availability in chem hydro... however, no doubt several folks will say coco is more like soil on a pH chart...but, I beg to differ seriously

10k, I have been giving some serious thought to this range you have advised. I think I have figured it out. My theory is this with my setup.

My problem arose when they were about 2 weeks veg under the heavy hitters; 1000ks. They grew up fast and became very hungry. I had to think about what was happening inside the pot of coco and I began to think back to all the runoff numbers I was getting. This all sparked when I was mixing nutes and as we all know, the ph drops as we add nutes and then I considered the opposite. Take away nutes and ph rises. When they were smaller and not so hungry I was feeding them at 600ppm and 5.8ph. I noticed that my runoff ppm at that time was not much lower, around 500. That means as my ppm's dropped the ph went up but not by much. As the ppm's went to 500 the ph probably went up to 6.0 which is in the acceptable range. Then I would fertigate again and it would go back to 600ppm and 5.8ph again. There were no problems then.

So, the plants got bigger and hungrier. Now feeding at 750ppm and 5.8ph and deficiencies show up. How could this be; I am doing nothing different? I remember my runoff ppm's at this time were dropping big time between feeds. They turned into hogs. I was getting runoffs of 400ppm. And that is where my problem started I believe. I had to consider what was happening in the medium (pot). If my ppm's dropped that much and I started with a ph of 5.8 then how high did my ph drift up to? I'm assuming that the ph must of been hitting at least 6.5. That is not acceptable. The range should be 5.5 - 6.1 to my experience. From previous experience I know that when my hydro rez has hit 6.2ph and up, leaves get all twisty and calmag problems show up. I am led to believe that my ph has been to high as the plants got hungrier. So, now if my thoughts are correct I understand your advice now. I need to start my ph much lower, say 5.3ph and as they eat between fertigations the ph will probably swing up to 6.0ph which is acceptable. I think I am on the right track and I have just fertigated with a 5.3ph. Will see what happens.

 

[bodhiseeds]

bump.....

 

[10k]

update richyrich ?

 

[Hydro-Soil]

So, the plants got bigger and hungrier. Now feeding at 750ppm and 5.8ph and deficiencies show up.

Because you're not feeding them enough.
1300-1400ppm @ .7 conversion
900-950ppm @ .5 conversion

Keep those nute levels in your res and you'll have a nice and natural pH swing that you won't have to adjust.

Read the thread on Lucas in my sig, explains exactly what you're seeing.

During days 20-30 they're feeding like crazy on mag so you'll need the pH to be higher in your coco to unlock that. Straight hydro you would raise it to 6.0-6.1 for a couple weeks until the buds have set. (Edit: Not familiar with coco so you'll have to adjust accordingly) After that you can drop it back down to whatever worked best before.

 

[richyrich]

Because you're not feeding them enough.
1300-1400ppm @ .7 conversion
900-950ppm @ .5 conversion

Keep those nute levels in your res and you'll have a nice and natural pH swing that you won't have to adjust.

Read the thread on Lucas in my sig, explains exactly what you're seeing.

During days 20-30 they're feeding like crazy on mag so you'll need the pH to be higher in your coco to unlock that. Straight hydro you would raise it to 6.0-6.1 for a couple weeks until the buds have set. (Edit: Not familiar with coco so you'll have to adjust accordingly) After that you can drop it back down to whatever worked best before.

I am running feed to waste and feed with every fertigation. No flushing because I allow plenty of runoff each time but I have to use a lower EC because of. Hence, I cannot treat this like a regular res.. I have no problems in hydro. They are looking great. My problem is coming from my coco plants. I guess I am still on the learning curve with this stuff and need to dial it in; I'm getting there.

I have read most of Lucas' threads. Good stuff.

Update:
Last 2 fertigations went in at 5.2 and everything is greening up. A little yellow but I take it they are turning around; takes a little while. Big difference though because they do not look like yellow zebras anymore.

Main problem -- ph to high. Now, I am gonna dial in their nute level. Gets tricky with a constant feed, no flush and lots of runoff.

 

[Hydro-Soil]

Main problem -- ph to high. Now, I am gonna dial in their nute level. Gets tricky with a constant feed, no flush and lots of runoff.

Wish I had more experience with coco. Mayhaps I'll get a chance to fix that.

Since you're going drain to waste and the medium is coco... wouldn't you be feeding them nearly full strength? I was under the impression that the coco doesn't really hold nutes. This would require full strength (or nearly) each watering. The less nutes it holds between waterings, the more nutes you'll need each watering.

By holding nutes I mean leaving nutes within the coco after the water is removed/dried/sucked-out. Re-wetting with new solution also puts some of that nute residue into the mix, making it that much stronger.

Does any of this help????

(Sorry, I'll go read up on coco this weekend!)

 

[richyrich]

I'm learning that coco can hold nutes but that the amount of runoff provided determines that. I like to not flush in between and just do large runoffs to the same effect. I was starting to see some tip burn at 750ppm (1.5ec) so I held there until I could get a handle on the ph. I think I can take them up a tad more which is nearly full strenght 900-950ppm. I'm dialing that in now. I read so much in the coco forum and the majority said that they just worried about the ph going in and that was it. I have to disagree now. But, I think it may have to do with water frequency. I hand water every 2 days in 3 gallon pots filled with canna coco only. Compared to the folks who water every day or multiple times a day probably don't get much of a ph drift in the substrate. I think that is where my problem was. I need a lower starting ph to allow a larger drift when watering less frequent. For now that is my conclusion. All the help was appreciated.

 

[afroman25]

I'm learning that coco can hold nutes but that the amount of runoff provided determines that. I like to not flush in between and just do large runoffs to the same effect. I was starting to see some tip burn at 750ppm (1.5ec) so I held there until I could get a handle on the ph. I think I can take them up a tad more which is nearly full strenght 900-950ppm. I'm dialing that in now. I read so much in the coco forum and the majority said that they just worried about the ph going in and that was it. I have to disagree now. But, I think it may have to do with water frequency. I hand water every 2 days in 3 gallon pots filled with canna coco only. Compared to the folks who water every day or multiple times a day probably don't get much of a ph drift in the substrate. I think that is where my problem was. I need a lower starting ph to allow a larger drift when watering less frequent. For now that is my conclusion. All the help was appreciated.

I'm having the same problem as you in coco. Im in 3 gal and watering every other day. I think part of the problem is the ph swing. I'm gonna drop my ph down to 5.0 and see what it does. I'll post the results after my next watering

 

[Hydro-Soil]

Stop using the Cal/Mag and your problems will become easier to fix.

FNB already has enough cal/mag in it, you just need to hit the pH range that unlocks it.

Edit: Sorry I didn't read that Cal/Mag in there before or I would have mentioned it.

 

[richyrich]

Here is how they look now.

 

[Seed Buyer]

Nice work richyrich! I am having similar problems w/ 3 gal pots of Pro-Mix and will try your "lowering the pH" theory.

 

[richyrich]

After seemingly getting the ph right, the last fertigation I had dropped the calmag. Today I walked into a bunch of praying tacos. They want more mag. I take it all that talk in the coco forums about coco holding onto mag is true. I am going back to adding calmag.

 

[10k]

Two things...
If the run-off pH is at or near 5.8...it's the weakest point for mg uptake.
If the coco has a salts buildup the sodium will block the cal & mag uptake

 

[10k]

This is THE accurate pH chart for showing element availability

And THIS pH chart which has been going around here at icmag is completely full of shit as far as showing nutrient element availability accurately.
Square bar chart sheeesh !