Coco rust spots, week 4 flower *PICS*

I'm having issues with my coco plant. She is in week 4 of flowering. This happened last cycle as well. I thought my light was too close but I'm starting to think it's a nutrient problem... Magnesium/Calcium? There are rust spots, interveinal chlorosis, and leaf tip/margin burn.

1 gallon pot of coco:

How long has this problem been going on? 4 days
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...) Coco Handwater
What STRAIN are you growing? White Widow
What was the establishing technique? (Were the seed or clone?) Clone
What is the age of your plants? 4 week veg + 4 weeks into flower
How long have they been in there mixture they are in now?(coco,soiless etc..) Since week 2 veg
How tall are the plants? 26"
What PHASE are the plants in? (seedling, vegetative or flower) are the plants in? Flower week 4
What Technique are you using?
What substrate/medium are you using?(Hydroton, RockWool etc.)
What is the Water temperature?
What color are your roots? White? Brown? Are your roots slimy? White
What Nutrient's are you using?(If growing soiless) GH Flora Micro/Bloom
How much of each nutrient are you using with how much water? 6/9 as per H3ad's Formula
How often are you feeding? (If using soiless) Every watering
How often are you giving nutrients? (If using soiless) Every watering
If flowering, when did you switch over to using Bloom nutrients? Same nutes since veg
What order are you mixing your nutrients? (example: veg nutes 1st, bloom 2nd ect) Micro, then bloom
What is the TDS/EC/PPM you are using? PH'd to 5.8.
What is the pH of the "Tank"?
Are you sure your calibration is correct on your equiptment? Yes, calibrated each watering
When was your last watering? Yesterday
What is your water temps?
When was your last feeding change? (ie. grow-bloom-micro-additional) Same since early veg
How often do you clean your system: example: Flush out water replace with clean water and nutrients?
What size bulb are you using? 1000w MH
What is the distance to the canopy? 24" or so
What is your RH Factor(Relative Humidity)? 40-50%
What is the canopy temperature? 82*
What is the Day/Night Temp? (Include flucutaion range) 82-72*
What is the current Air Flow? (cfm etc.) Sealed room
Tell us about your ventilation, intake exhaust and when its running and not running ? Sealed room
Is the fan blowing directly at plants? Indirectly and oscillating
Is your water HARD or SOFT? Hard. 200 PPM.
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water? Tap
Are you using water from a water softener? No.
Has plant been recently pruned, cloned off of or pinched Yes they were recently pruned but this started before
Have any pest chemicals been used? If so, What and When? None
Are plant's infected with pest's No
Whole plant shot. She is flowering just fine and as you can tell it is affecting only the old fan leaves.

Shows interveinal chlorosis and some rust spots.

Rust spots up close. Noticed they are primarily on the margins of some leaves and all over others...

Shows rust damage all over leaf as well as margin burn...

Yes, they look like they could use more magnesium, more so than calcium. Maybe your plants are just mg whores and need a bump with an added 1/8th teaspoon (per gallon) epsom salts, the initial fast fix here. But at the same time, they're also looking pretty hungry too.

In the h3ads formula (a 2m/3b mix), you really shouldn't be seeing a mg problem. That formula has more mag and micros than the lucas (1m/2b) formula, which leads me to believe your nute solution pH needs lowering or its been damaged with too many elements percipitated out in mixing and pHing and thus unavailable to the plants.

In coco you have a hydro situation, so I would also go with a lower target pH than the 5.8 pH that you've been starting with, and allow it to swing through the range instead of trying to hold the 5.8 pH. Starting with a 5.1 and letting it swing to about 5.9. It will give the mix a better chance of the cal and mag being more available for the plants. I believe you'll see an overall color improvement if your pH were lower. In fact, they might start looking a lot less hungry when they start working at a lower pH. For the above reasoning, It would be good to know what kind of runoff pH you're seeing from that coco to know how high its swinging ?

Why a 5 to 6 range is better...
Excerpted from Flairform...

It is over this pH range that all growth factors produce optimal growth. If the pH is allowed to rise much above 6.0, more than half the essential nutrient species (especially calcium, sulfate, and the trace elements copper, iron, manganese, and zinc) can precipitate, thus becoming immobile and unavailable for transport by the water flow to the roots.

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So...If they're still looking hungry after the cal/mag isssue is fixed, you might want to step up that h3ad strength some too...
A a '6, 9' mix is basically a '2parts M to 3 parts B ratio, so bump up the mix accordingly.

hth,
10k

ps... I'm sure someone will just jump in here any second and say something like "just give em some cal/mag" arrgh !

I would most defiantly agree with 10k....... BUT there is one thing I must stress.......

You know what, I am going to try something here...... long time ago I seen a guy with this exact same problem, this may sound crazy here but just try this, because you don't have anything to loose....... but if your water is 200 ppm is this the correct amount before or after adding micro?

I have 2 things on this saying........... I am not exactly sure as of now, until I get the info I asked above......... but

Let's say that is the ppm out of the tap, you add micro with it and increase it...... in the past I have seen issues like this, it's not to often, but this looks like it would be hard water damage..... that is if your using tap at 200 ppm and then adding micro.

A guy was growing in hydro and using around 250 ppm and adding around 100 ppm micro and I could have swore up and down it was an issue with calcium, his ph was correct; he even went and kept it and adjusted it and kept it there and to nothing no fix..... then I was looking through some pictures I had in some discs of problems back from overgrow and it occured to me that hard water damage can mimic calcium, because like 10k said it looks like magneisum and calcium; which I will agree with him...

but I would first try to adjust the pH FIRST and see if this solves the problem, because there are strains that don't like certain pH's, which is why there is a range you can use.

Try the pH 10k has listed, because he is correct about that.

If you find the issue is still spreading with pH adjustment and you know 100% it's correct and not working.......

then try getting a hold of some lower ppm water, not tap and then use the micros from your nutes.....

I may sound crazy, but I thought I would just put in my 2 cents just in case 10k's advice did not work.... which I have only seen 1 time in like over 10,000 of his posts so 99.9% of the time 10k is correct.... I will agree with him on this... but like I said if your adding micro to your tap water and using it like that I would first stop using tap water and get low ppm water and add the micros from your nutes, this is ONLY if pH adjusting is not working for you.

Or you could skip with the pH adjusting try keeping it where it is at and try ditching the tap water and get low ppm water and using the nutes.

Yes, my water is 200 PPM right out of the tap (cold). Ironically I was going to use RO but everyone says it is significantly harder to grow in coco with than tap.

So you're saying it's possible that the high PPM tap + micro raises the TDS of calcium and other micronutes too high? Is it possible that using hard water micro would solve this? I can get a RO machine, I'm just wondering if hard water micro would serve the same purpose.

I like the idea of a pH swing. We are implementing ebb and flow tables in less than a week and being able to let the res swing from 5.1 to 5.9 would make life much easier on us.

Again I have to say thanks to 10k and Stitch for the advice. I think I have been going bald over this.

-XIII

As long as you have micro supplements to give the plants when using RO, you will not have a problem. You can also go tap/ro mixture to save if you have to go buy water by the 5/10 gallon jugs.
Many people do this.

RO water is low pH and you will have much better control over what you give your plants.
You can go either way, it's up to you, you could try removing the micros and just use tap, this does not always work......

also hard water most of the time has a high pH, one thing you do not want growing in coco.

I have seen hard water damage in plants and it very well does mimic calcium deficiency.
Have you tested your mixture with micros and your tap to get the final ppm?
Personally I Have not used hard water micro.......
I have also seen people use tap for hydro, but there ppm was not over 150 and not have to supplement with cal mag and other micros.

Other situations I have seen people use tap water over 250 and show the same issues you have and stopped using tap water ( hard water) and gained complete control back over there grow..... this is why I stated it's something to try, because most people who grow hydro use RO,distiled or low ppm (soft water) tap.

So you have a lot of choices you can try that 10k has stated too.

It's up to you which way you feel comftable about going, because everyone has different growing style..... one thing I will say with a pH of 5.8 it should not look like the way it does.

So If you want, I think one of the easiest ways to try to rid of this and get the pH lower.

Try using some RO or low ppm bottled water that has no sodium added and then add your micro solution.

or Lower your pH to the range 5.1-5.5 and stop using the micros and just use the tap for now.... if that does not work, add the micros with it, but chances are very high that it may not work due to high micronutrients in the water......
but, from what I have learned is, nothing is impossible and nothing can be ruled out, cause there is always something small that can cause a problem to become big, which is why I ask a million questions to ensure I get the whole story.....


Have you tested your pH out of the tap? How often do you monitor your pH?


So imo, either you have too high micronutrient concentration or your pH is out of wack.

Even if you change your pH correctly, that is still a high amount of micros to use and it will be over 200.

That is getting up in the range where it can cause problems..... hard water and hydro/soiless mixtures/coco and so forth do not mix well.

Something I have neglected to mention but really should have! This problem only happens a few weeks into flower. I have heard plants need a lot of magnesium after the stretch. If you look through my current 1kw grow, which had the same problem, you can tell they were in perfect health until about the 4/20 update.

I'm seriously considering getting an RO unit now. Would make everything more consistent, and would have to use less pH down.

Just to clarify, by "micro" I meant GH Flora Micro. I have cal-mag but thought it wouldn't be necessary in 200+PPM water!

"If the starting water is above 200 ppm, that is pretty hard water, that will lock out mg with all of the calcium in the water. Either add a 1/4 teaspoon per gallon of epsom salts or lime (both will effectively reduce the lockout or invest into a reverse osmosis water filter.
Mg can get locked-up by too much Ca."

Would it alternatively be possible to just supplement with extra epsom (magnesium) to offset my tap water's high calcium?

pH out of the tap reads 6.4. We calibrate and use our oakton eco every watering.

So I guess my best option would be to get an RO unit next cycle? The pH swing advice makes sense but if too high PPM tap water locks out magnesium it seems my only option, correct?

A lot of people use hard water to water there plants, but since your growing in coco your growing style is going to be that of hydro setup.

Water is going to be a big role here your water pH is too high it needs to be lower, you have to options of lowering your water pH........ RO water or get some pH down.

Yes, they use a lot of magnesium during there stretch, some strains are magneisim cows.
WIth your ppm your using, you should not be having any deficiency of calcium or magneisum..... so honestly I think you should try getting some bottled water or get some RO water and test it, you can get it from stores and such.....

Just add some eosom salts to it, lime can be added, but epsom salts is much easier and I would use that with the way your growing setup is.

It's hard to keep your pH stable with hard water due to high calcium/mag and other micros in it..... It always wants to rise back up and most people would fix it by using pH down, but they end up building it up and causing problems, so honestly i would try not using the tap water and get bottled water/ro....... You can mix them 50/50, but since you got micro nutes I would try first not using tap in the mixture just yet.

Whaaaaaaaaaaaaaaattttt ?

10k said:

Whaaaaaaaaaaaaaaattttt ?

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Alright Stitch, you've convinced me, I'm gonna get an RO unit after this harvest!

Thanks for your continual help, I researched this for quite a while and couldn't even diagnose it.

I agree it would be a lot easier to start from a blank slate with RO water and work from there with epsom salt. I remember reading the ENTIRE "H3ad goes Coco" thread (wondering what I was doing wrong!) Anyways I remember h3ad stopped using the epsom to no ill effect, but I know his plants might not need as much mg as mine.

10k said:

Whaaaaaaaaaaaaaaattttt ?

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ehh??? Which part of what did I say wrong?



XIII: You do not have to buy an RO unit; there are places you can buy bottled water im jugs and so forth, cause I know RO units can be pricey!
I had to cart water from wal mart's RO center they had, 20 gallons of water a month; I got so damn sick of it man; it killed my back carting water like that for a year. We mainly used it for plants and using it to cook,drink and so forth.....
As long as you get water that is RO/bottled ( make sure sodium is not in the water) you will be alright.
Here is the way I look at it, it's been known ppms over 200 tap water that is can and has contributed to hard water damage, it also known to cause other issues with the way NPK and other nutrients are absorbed, for your plants to show magneisum deficiency and a little bit of calcium deficiency like 10k said which I agree with his entire post he posted....... with your ppms over 200 including your micro nutrient your using; that right there is already high, so either A too much micros or B pH is too high not allowing absorption, so then B ends up coming back around using lower PPM water and supplementing with micronutrients like you have been doing.

With you using coco as well, your tap water pH is already over it's limit, with lower ppm water you have much more control over your pH and much less headache in the end.

That right there with you using coco the pH needs to be 1.1 pH lower than your out of faucet tap, then with you adding micros to that I know the pH will even increase more with just the tap and micros.

Update: Bought a 100 GPD Hydro Logic machine. Flipping another cycle to flower in a few days. When we hit the 4 week mark where this would normally occur I will update with the (hopefully good) result. I definitely think that this helped. Thanks to 10k and Stitch for the advice!

-XIII

Ya, keep us posted I would love to see how they turn up once they recover!

XIII and how's the situation now?

Beautiful explanations lots of combined knowledge here.. it just confirms what i had thought and strengthens my arguement(with myself) to get a R/O unit.. Nice to have your thoughts/beliefs confirmed, and learn a whole shitload more..

Great posts guys, thanks for the awesome info

I think I got similar problem

...so I'm curious, how did XIII fixed his.

Using the H3ad formula in coco requires supplemental Mg! Most use Cal-Mag, but I use epsom salts just cause it's cheaper.