Yellowing leaves/Green veins

This is probably something quite straight forward but...

Leaves are yellowing leaving green veins.

These cuttings have been vegging for a little over three weeks in 1 litre pots of Canna Coco. They began with an ec of 0.6 which has slowly increased to 1.0 currently.
I feed per week is replaced with plain phed water.
Feed is Canna Coco a&b.
2.5 ml Cannazyme per litre.
I can't tell the precise ph but the mix shows the usual pissy yellow with my checking kit thingy, same as I have used for three years or more so it should be okay.
First pic is the worst example which has developed over the past 7-8 days.
The last pic is one which has just begun to change a day or two ago.

Advice would be appreciated

Okay. My first ever time at loading a picture has failed. Please bear with me while I try again...

sundays child said:

This is probably something quite straight forward but...

Leaves are yellowing leaving green veins.

These cuttings have been vegging for a little over three weeks in 1 litre pots of Canna Coco. They began with an ec of 0.6 which has slowly increased to 1.0 currently.
I feed per week is replaced with plain phed water.
Feed is Canna Coco a&b.
2.5 ml Cannazyme per litre.
I can't tell the precise ph but the mix shows the usual pissy yellow with my checking kit thingy, same as I have used for three years or more so it should be okay.
First pic is the worst example which has developed over the past 7-8 days.
The last pic is one which has just begun to change a day or two ago.

Advice would be appreciated

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pics

poss could be due to cold nights temps bothering roots..just op..good luck

Thanks for chipping in, Azed but I don't think it's temperature. I should have mentioned earlier that thry are under 24/24 light and temps are steady 75-77 f.

sundays child said:

Thanks for chipping in, Azed but I don't think it's temperature. I should have mentioned earlier that thry are under 24/24 light and temps are steady 75-77 f.

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No way we could have known that. That's why there is a form stickied in the infirmary. Fill it out please?

What STRAIN are you growing? Critical from Royal Queen.

What was the establishing technique? (Were the seed or clone?)Clone

What is the age of your plants? Three weeks past rooted.

What PHASE are the plants in? (seedling, vegetative or flower) are the plants in? Vegetative

What Technique are you using? Topped to leave four main stems.

What substrate/medium are you using?(Hydroton, RockWool etc.) Coco
What is the Nutrient temperature? Luke warm/
What Nutrient's are you using?Canna Coco a&b
What is the TDS/EC/PPM you are using? Currently at 1.0 ec

What is the pH of the "Tank"? Hand watered/no tank/see above regarding ph

Are you sure your calibration is correct on your equiptment?Yes

When was your last watering? Today.

When was your last feeding change? (ie. grow-bloom-micro-additional)Upped from 0.8 to 1.0 ec three days ago.
What size bulb are you using? 600 hps.

What is the distance to the canopy? 12"
What is your RH Factor? 40%
What is the canopy temperature? 80f.

What is the Day/Night Temp? (Include flucutaion range) 75-77 room/77-80 canopy

What is the current Air Flow? (cfm etc.) 230 cfm

Is the fan blowing directly at plants? Yes

Is your water HARD or SOFT? Hard

Has plant been recently pruned, cloned off of or pinched Topped 10 days ago
Have any pest chemicals been used? If so, What and When?

Are plant's infected with pest's No

First off, I wouldn't have those only 12" away from a 600.

Looks like a Mg def I think combined with a K def.

Pissy yellow using pH drops? Sounds like 5.6-6.0? I like a little greenish in there. Assuming you are using enough nutes Mg defs are caused by drop in pH. Snype says below 5.7 your screwed, I say below 5.5. However using drops running on the low side is dangerous in coco. I'm not a big fan of using plain water every so many waterings. It could cause deficiencies. I just go a little lighter on the nutes and ALWAYS supplement my nutes with Mg and K in coco. esp Mg.

pH could drop from nute concentrations if you don't water daily in coco too.

Thanks Hazy. 'm running everything as I have in previous grows. The shade is a Mantis, gull wing type with a heat shield but I have now backed it off another 6".

The only difference this time round is the Critical which I've never run before.

Given your thoughts about deficiencies I'm wondering if my nutrints are stale or something. They must be over a year old by now...

1. There are different conversions on EC meters, would you happen to know the conversion of your meter or what the PPMs are?

2. What is the height of your plants in inches?

3. I can't tell from the pics but can you tell me from the margins of the leaves are they curling up or down?

4. I see that you topped your plants 10 days ago. Did you have the problems before you topped and when did the problems start happening?

5. What temperature is luke warm?

6. Can you tell me exactly how much of each nute you used per gallon and exactly how you mix your nutes?

7. I see that you are using pH drops. I personally don't like these drops and I'll tell you why. They are not that accurate at all in my personal experience with them. You are running a new strain right now and that seems to be your only difference from your past grows. In my personal experience with cannabis plants, each strain reacts differently to pH levels and swings so just because you're doing the same as the past doesn't mean that they will react the same. For example, I was running Shiva Skunk for about 10 years and the mom that I took could handle crazier pH swings and nute swings than other strains that I run. I just ran some Blue Cheese and they were so sensitive and could not handle any swing at all without showing very poor signs. In my opinion it's easier for me to diagnose your problems when I know what the exact swing is to the exact points but I will do my best in helping you out.

8. How were hour nutrients stored during the past year? Where they subjected to freezing temps or extremely high temps?

Still reading and updating.....

Note: Hazy seems like a very smart guy and I trust some of his opinions from what I've seen from him in the past (even though he likes to Neg Rep me). I'm saying this because I see that you are not online right now and I don't know how long I'll be here for to receive your answers. If for some reason I'm not here and Hazy is willing to help you, when he has all the info I would try and trust his opinions.

Another IC member that I trust is PuReKnOwLeDgE and I want to give you a statement that he gave someone else because I agree with him on this issue:
"In soiless watering twice a week, I would water half strength of whatever PPM I was trying to achieve.

EX: If I was trying to hit 600 PPM and was watering twice per week I would water with 300ppm strength solution.

Most people running soiless, but I do not speak for everyone, either water 1/3 strength each watering or water full strength weekly with straight waterings in between."

Another member that I really trust also is Massproducer and he seems to have a lot of experience with dealing with plant issues.

I can't guess on this, if it were me I'd fear over feeding although that doesn't appear to be the obvious conclusion. Seems the TDS is low, a lot of organic foods test dissolved solids that are not at all nutrients. That is why people love organics, it adds so many more products that add to character/robust nature.

I just can't tell without you adding to your information how strong you are feeding when compared to your nutrient bottle. I add a lot more than just one product, so that is why if it were me I'd assume over feeding.

you should water your coco every day or you risk buildup of nutes(from the drying) and thus dropping pH in the medium which can cause this.

Snype, thanks for your input. I'll do my best to answer your points.

1) 1.0 EC = 500ppm on the 500 scale and 700ppm on the 700 scale.

2)Plants are about 9 inches high.

3)There's no leaf curl and they look norman apart from the colouring.

4) The problem began 2-3 days after topping.

5)I have no idea what temperature like warm is! It's not chilled and it's not warm. When I stick a finger in the bucket it doesn't feel hot or cold. Sorry to be so vague!

6) I work in litres and mix nutrients in a 10 litre bucket which equals 2.64 US gallons. For EC of 1.0 I use 12 millilitres each of both A and B.
I ph the water first with 2.5 ml of ph down, stir, add A, stir again, add B, stir again, add 25 ml of Cannazyme, stir again.
I usually make this up in 8 litres of water, leave it for a few hours then ad 2 litres of warm water to take the chill off it, making it 'luke warm'.

7) If I understand ph swing correctly, it happens in an automated. recyling system when a reservoir/tank is used. I hand water/feed and mix fresh nutrients each day - except one day a week when I give plain, phed water.

8) The nutriens are stored in an unheated room indoors. It hasn't been overly cold or warm in there.

As I water/feed every day, I'm not sure what your point about the strength/frequency of watering means in my methods...

Thankyou for your help in this.
Thanks too to Hazy. I hear your point about not using plain water. It's something I learned on here and I do it insteaad of a weekly flush. It has worked okay for the past year or so.
Thanks also to Lysol for the heads up about the form.
And thanks to Organic monkey though as I'm not working in organics I'm not sure how appropriate it is.

I'm leaning towards Magnesium deficiency. For $15 you can get a liter of Botanicare's Cal-Mag Plus. Use this at about 3ml per Liter during veg (12ml per gallon). Crank it down during flowering because it does have a fair amount of nitrogen.

I used Canna Coco A & B 15ml per gallon of each with Cal-Mag+ 15ml per gallon and had really great results. The moment I stopped using the Cal-Mag+ I saw a calcium deficiency pop up, and then everything else followed.

I can't tell the precise ph but the mix shows the usual pissy yellow with my checking kit thingy, same as I have used for three years or more so it should be okay.

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... and your testy kit thingy is what exactly? yellow on the GH drops means 6.0, on ones you get at walmart it might mean 7.0, I like to keep my coco between 5.5 and 6.0 (so orangish)

also..

What is the current Air Flow? (cfm etc.) 230 cfm

Is the fan blowing directly at plants? Yes

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That's a hell of a lot of air to be blowing directly at the plants, not saying that's your issue though.

Is your water HARD or SOFT? Hard

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Hard water has lots of Ca that locks out Mg. How hard is "hard"? Can you try switching to RO?

8) The nutriens are stored in an unheated room indoors. It hasn't been overly cold or warm in there.

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uncovered? this could allow water to evaporate, throwing off the Ca:Mg ratio further.

I think the above posters are right. Mg is locked out. But I would disagree that it is deficient, I would say it is locked out. I would highly advise not adding additional things like epsom salt until you fix your hard water problem. Adding more Mg won't change the PH, and we will only lock out Ca faster (expect that to maybe happen anyways because the problem is so developed)

So again my recommendations are let the PH dip a little lower (if in coco), use RO, distilled, or some sort of soft water, and dont let it sit out uncovered more then a week. Even if I've totally missed the problem, none of these recommendations should hurt you, only help.

lysol said:

... and your testy kit thingy is what exactly? yellow on the GH drops means 6.0, on ones you get at walmart it might mean 7.0, I like to keep my coco between 5.5 and 6.0 (so orangish)

also..

That's a hell of a lot of air to be blowing directly at the plants, not saying that's your issue though.

Hard water has lots of Ca that locks out Mg. How hard is "hard"? Can you try switching to RO?

uncovered? this could allow water to evaporate, throwing off the Ca:Mg ratio further.




I think the above posters are right. Mg is locked out. But I would disagree that it is deficient, I would say it is locked out. I would highly advise not adding additional things like epsom salt until you fix your hard water problem. Adding more Mg won't change the PH, and we will only lock out Ca faster (expect that to maybe happen anyways because the problem is so developed)

So again my recommendations are let the PH dip a little lower (if in coco), use RO, distilled, or some sort of soft water, and dont let it sit out uncovered more then a week. Even if I've totally missed the problem, none of these recommendations should hurt you, only help.

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The test kit is one the same I have used since I began growing. It's worked fine through several grows.

That's the extraction fan. The occilating desk type fan blows over the plants.

I don't know how hard. It leaves calcium depeosits on the kettle. RO isn't possible. Again, it's worked fine through several grows.

All nutrients and addatives are kept in their original bottles with the lid on.

I have grown seven different varieties all to reasonable success using pretty much the same methods. I'm confident that my environment, medium and water are fine.

I will drop the ph a little for the next week or so and see what happens. At the weekend I'll buy a ph meter and some fresh nutrients.

Thanks again for you help. Do you think I should flush them before feeding at a lower EC and ph?

I had very similar issues early on in my E&G my leaves were almost flourescing. Turns out, since I use RO water, I was lacking in Mag...so, every res change in my 55 gal res, I add a cup of CalMag and my problems went away.

sundays child said:

At the weekend I'll buy a ph meter and some fresh nutrients.

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That's probably the best idea. If you can get a 2 in 1 and also measure your water, water quality does change over time.

Thanks again for you help. Do you think I should flush them before feeding at a lower EC and ph?

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I'm impartial in that regard. I just know that hard water is one possible way for Mg to get locked out (you observed Ca deposits, Ca in abundance locks out Mg.)

RO water should be an option. I pay $1.50 for 5 gallons at one of these things when I get Mg deficiencies, I switch back to tap water after the plants recovered. You can also cut the RO water with tap water to make it last 2x as long.

Knowing nothing about your nutes, I would switch to RO water and add cal-mag only if the plants still need it

Thanks again, Lysol.
I really don't want to go the RO route. I know it's common in the US but our water quality is much better generally in the UK. If these Criticals are just over sensitive, I'd be better off just going back to a tried and trusted variety.
For now I'll try the ph drop.

I wonder if Hazy and Snipe have anything to add...?

The only thing that comes to mind to me is an Iron problem but let me do some research for you.