Fert burn or K deficiency?

Hello growers! :)

This is my first post here in this great forum. I've been reading a lot and started my first grow, and until now I had no problems.

Last week two of my plants started to develop burn tips on some of my lower leaves. It quickly spread to most of the leaves, some with more intensity and others with less.

I read a lot and saw loads of pictures of problems and deficiencies, but could not deicide if this is a Nute Burn or some kind of deficiency (Potassium?). It's hard for me since I never saw any of them in real life (first grow!).

Hope you guys can help me!

Here is the Troubleshooting form followed by some pictures:

E-indoor or outdoor = Indoor
E-soil, soilless, coco, aero, or hydroponic = Soiless
E-specific medium = SunshineMix + Perlite
SCL-Anything you have added to the soil = Perlite
SCLR-Soil or slab runoff pH = 6,3
E-Water source = Mineral Water
E-Source water pH = 6,7
E-Age of plant = 5 weeks and 3 days
E-Type of fertilizer = Biogrow (Biobizz)
E-Rate of application = 1ml/L every watering, then when the problem appeared every other watering
E-Lighting source and distance from plant = 400 W HQI, a palm distance from the tops.
E-Air temperature (both day and night if you are running a dark period) = 82,5F (day), 79F (night)
E-Air % Relative humidity = 68% to 75%
E-Lighting schedule = 18/6
E-Type of ventilation your room has = One large fan taking air from the cooltube and grow, one smaller fan bringing fresh air, plus one small fan for air circulation.

Thanks for the help! :smokin:

i highly doubt it's fert burn as it's pretty hard to burn with organics. i've been using the biobizz line for a few grows now, with no burn issues. you especially shouldn't have any issues with that application rate.

i definitely think you have another issue.

your plant looks small for 5 weeks. this is possibly related to the high humidity.

not to mention, i'm not too found of your light. have you used this before or seen decent results from one?


-shake

Thanks for the reply, Shake! :)

Good to know it's not fert burn. One less thing to worry about!

About the humidity, I have an dehumidifier inside the room and even this way I can't lower it more. Do you think this can be my problem? Which humidity should I target?

Someone said in another forum that my PH is to high and I should lower it to about 5.5 . Do you agree? (always thought that ideal PH was between 6.0 and 7.0)

About my lights, here in my country it is very standart to use it on the veg stage... Which one do you recommend?

I'm posting some more pictures of the two porblematic plants fo you to judge the sizes and the problem better.

Thanks again for the help! :smokin:

6.7 water pH is a bit too high for soilless, bring down to 6... 6.5-6.7 is ideal for soil, but soiless is lower.

If water is too hard it could be a problem.

Light is too low, they can't use so much light until they are healthy. Even then, a palms distance is very close to a 400 mh. Having the light so low right now is causing additional stress. I'd give them a couple feet at this point.

If there isn't enough air circulation it'll make things even worse, make sure you can see the leaves moving in the breeze.

They also probably won't need more food until they are healthy. They are really small for 5 weeks, so they haven't been using much nutes, but if you keep adding they will build up. It can't hurt to do a soil test and see where your pH is at, as well as if NPK is too far off...

Hi Dorje, thanks for the reply!

The water I'm using has a PPM of 30. I don't think is to high, right?

Thanks for the tip about the light height. Will correct.

I already tested the PH from the soil (from the runnof) and it's about 6,3. To high, right? Which value shoud I aim for?

So, should I keep giving them water only (with the PH regulated) and wait until they get better to start feeding again? Is there anything else I should do?

Many questions, sorry! ;)

Thanks for the help!

Someone else can help me, please?
What you guys think about the PH?

Thanks!

Not sure about the runoff pH, but the water you give 'em should be about 6. You can adjust this easily.

If you can find a soil test kit, I'd buy it and test your current soil pH and NPK.

Sure wish you folks that offer advise would give the correct advise.
6.3 to 6.8 ph for peat-based mixes. Keeping it below the low range and you will lock-out nutrients.

Soilless is a long-used term denoting any potting mix not made from garden dirt. The most common are peat moss based mixes, and are usually buffered to a near-neutral ph. Trying to lower this ph is unnecessary, unwarranted and depletes the buffers in the soil quicker. Sunshine is a peat based mix.

Then you have coco, hempy bucket, aero and hydro. Methods I do not use, but I hear they require a lower ph.

What do the instructions on the bottle say about dosages and frequency of use? Most nutrient products give a weekly schedule. (one application at recommended dosage per week) None I've come across are a 'feed every watering' formula.

Your growroom would benefit from proper lighting. Incandescents, HQI's, grow spotlights are all garbage in the growroom. Too much heat, wrong spectrums. CFL's, fluorescent tubes or HID lights are optimal. (in the correct spectrums, of course)

Thanks for the reply and advice, guys! :thumbsup:

Quote:

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Originally Posted by Rusty Trichome

6.3 to 6.8 ph for peat-based mixes. Keeping it below the low range and you will lock-out nutrients.

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So, if PH and fert burn are not the problem (burned leaves), what can it be?

Quote:

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Originally Posted by AnomanderRake

So, if PH and fert burn are not the problem (burned leaves), what can it be?

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Quote:

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Originally Posted by Rusty Trichome

What do the instructions on the bottle say about dosages and frequency of use? Most nutrient products give a weekly schedule. (one application at recommended dosage per week) None I've come across are a 'feed every watering' formula.

Your growroom would benefit from proper lighting. Incandescents, HQI's, grow spotlights are all garbage in the growroom. Too much heat, wrong spectrums. CFL's, fluorescent tubes or HID lights are optimal. (in the correct spectrums, of course)

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That's still my answer. ^^^

Humidity is a little high for me, but I've seen worse.

Quote:

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Originally Posted by Rusty Trichome

That's still my answer. ^^^

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Well, Biobizz say that you can use Biogrow every watering if you want...

About the light, I can tell it was a surprise for me. It's my first grow but here in my country I've seen a lot of peopple using it as the default for veg (HPS being the default for bloom). I will chek the ones you said out but do you think HQI light may be causing the problem with the leaves? In fact, only 2 of the plants are having this problem...

Thanks again!

Quote:

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Originally Posted by Rusty Trichome

What do the instructions on the bottle say about dosages and frequency of use? Most nutrient products give a weekly schedule. (one application at recommended dosage per week) None I've come across are a 'feed every watering' formula.

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Right as rain here. ONE application of recommended dose per week is all that's necessary. Especially in veg!! I've used BioBizz for a couple years and the only time I ever double up on a feeding in one week is from about week 4 to 6 of flowering. BioBizz isn't the most aggressive nute system available so I like to pack a punch in the middle of flower.

The rest was of course spot on too, just didn't want to quote the whole thing:thumbsup:

Anomander, consider yourself lucky Rusty stopped in to help you.

BTW, you said your tap PPM is only 30 right? Might want to look into some CalMag to add with it. BioGrow doesn't contain them to my knowledge. I had a small lightening once when i used BioBizz and bottled water. Went back to my tap at 280ppm and it cleared things right up. Found out later on that the bottled water only had about 15ppm in it.

I am very greatfull for all the advice guys! :thumbsup:

.. But I am a little confused... Is the problem with the leaves caused by using biogrow every watering, biogrow+bottled water, wrong light... All the above options? :p

thanks!

Quote:

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Originally Posted by AnomanderRake

Ibiogrow+bottled water

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IMHO and experience it's this one. Though all of them may be contributing factors, I know for a fact through experience that those 2 don't play well together. You must have Calcium and Magnesium, if you don't, it'll only get worse because the plant needs even more CalMag in flower.

Just my :twocents:

Thanks a lot!

One more question: my tap water smells of chlorine. Is it a problem for the plants?

I've personally never had a problem using HQI Metal Halides, and the double-ended construction actually makes for a smaller-profile lamp. I've always used HQI on aquariums, as they penetrate hardcore through water, and I've found them to be just as effective in the grow room.

It isn't just one issue, it's a combination. Nothing devastating, but a slow build-up of issues. Tiz part of the learnin' process though. :cool:

If you are going to feed every watering, you'll have to adjust dose so you are giving the same ammount of nutrients per week. If bottle says 1 tsp per gallon per week, then two waterings with 1/2 tsp per gallon is acceptable.
1 tsp per gallon every watering would kill the ladies. (this is just an example, not actual instructions)

Quote:

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Originally Posted by AnomanderRake

Thanks a lot!
One more question: my tap water smells of chlorine. Is it a problem for the plants?

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Let it sit-out (uncovered) overnight. If it still smells like chlorine, they are using chlorine solids in your municipal water system, which would need filtering-out. (reverse osmosis)
I use molasses instead of CalMag.

Quote:

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Originally Posted by khyberkitsune

I've personally never had a problem using HQI Metal Halides, and the double-ended construction actually makes for a smaller-profile lamp. I've always used HQI on aquariums, as they penetrate hardcore through water, and I've found them to be just as effective in the grow room.

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You should try some 'good' lighting sometime. You'll never go back. :thumbsup:
Having kept coral and reef tanks, I'm very familiar with trying to use aquarium lighting and equipment for my growrooms. (HQI's, pumps, bubblers, actinic bulbs, 4-pin fluoro's...) HQI is a sub-par choice. Given a choice between HQI and CFL's...I'd go with the CFL's. At least you can provide the correct spectrum(s) and the heat usually isn't an issue.

Thanks Rusty for the help! :thumbsup:

"You should try some 'good' lighting sometime. You'll never go back."

Why do you think I went LED? ;)

Perhaps LED's are the wave of the future, but for now I'll stick with my CFL's for veg, HPS (and UV) for flower. Only thing that beat's it is growing outdoors. And then...just barely.

I've followed Str8's LED grow since his return from overseas, and yes...good buddage is possible. :thumbsup: He's done one hell of a good job, especially with a budding new technology which is still being dialed in and perfected. (as an industry)

Quote:

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Originally Posted by Rusty Trichome

Sure wish you folks that offer advise would give the correct advise.
6.3 to 6.8 ph for peat-based mixes. Keeping it below the low range and you will lock-out nutrients.

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Didn't see it was Sunshine Mix, just saw soilless. My Bad. Rusty is right as far as the pH range. Kinda confusing having 2 places where you list the medium though...

edit... make that THREE places :wtf:

"Only thing that beat's it is growing outdoors. And then...just barely."

Which is why my puny 50w LED panel caused light bleaching on my plants, though I'm only putting 1/3 the power per square foot the sun will do through the atmosphere at sea level?

I think I'll stick with my LED panels when they can put out enough pure power to bleach plants under ~75-80 degree temps.

About two months ago, I was given the privilege to see/feel/toutch/taste and smoke LED grown cannabis. The grower isn't a newbie, and has a pretty firm grasp on his equipment, nutrients and genetics. Twas good smoke, tasty and stony.

I'm not at all knocking LED lighting as a growing trend with potential, but my major issue is it's yield. It's nowhere near the yield with HIDs and it's still in the experiment and testing phase of it's development. Speaking of which, if it's damaging your ladies, you might want to re-think your position, lol.

I stand by my assesment. ;)

So Anomander...what do you think?

"It's nowhere near the yield with HIDs and it's still in the experiment and testing phase of it's development."

I've seen other grows where custom-built LED panels smashed any HID grow (besides vertical.) We're pretty much at LED smashing HID for yield from wheat crops to cannabis crops.

"Speaking of which, if it's damaging your ladies, you might want to re-think your position, lol."

More like rethink the actual positioning of my panels, I'd suppose :) 50w causing burn from 2 inches, 120w causing burn from 9 inches.

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Originally Posted by khyberkitsune

I've seen other grows where custom-built LED panels smashed any HID grow (besides vertical.) We're pretty much at LED smashing HID for yield from wheat crops to cannabis crops.

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Perhaps with links and documentation I'd acquiesce, but it does sound a lot like the arguments when CFL's were first gaining in pouplarity. However, they were/are an affordable risk.
As I said, I'm hopeful about future generations in the LED realm, but you make my point for me. "Pretty much" there isn"t "there". Once LED's get "there" and the price goes down, perhaps I'll give it a whirl. Until then, on my budget...out of the question.

Seems we've taken over the thread. Oops. <sorry>

Quote:

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Originally Posted by Rusty Trichome

So Anomander...what do you think?

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Well... :D
I am a n00b in all this, but inspired by Rusty CFL talk I am building a clone + mother mini-grow only with CFL lights. Let's see how it goes... :rasta:
But I confess LED seems very promissing!

About my girls, I can tell the problem is gone now. All the new leaves are growing without burns but the old ones didn't recover.
It is still a mistery what happened and I don't now if I actually fixed (and how) or if the problem went away.

The only two things that I did was:
1- Stopped using mineral water (changed to tap with 48h rest)
2- Start balancing the solutions to PH 6.0, instead of 6.5/7.0 like before.

One thing about my soil mix that I think you guys maybe missed is that I'm using 50% of perlite with it. Doesn't this make it work more like hydro? Without nutrients? Maybe thats why the slight lower PH worked better?

Thanks again guys! :smokin:

Quote:

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Originally Posted by AnomanderRake

The only two things that I did was:
1- Stopped using mineral water (changed to tap with 48h rest)
2- Start balancing the solutions to PH 6.0, instead of 6.5/7.0 like before.

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So do you still feed with every watering? How much and how often?
Ditching the mineral water is a good idea. Too many minerals and metals. Did you know some contain uranium...?

Quote:

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Originally Posted by AnomanderRake

One thing about my soil mix that I think you guys maybe missed is that I'm using 50% of perlite with it. Doesn't this make it work more like hydro?

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Why, are you watering them like they're hydro?
No, I didn't miss the perlite. And nope, it's not anything like hydro. And I suggest you keep your ph in recommended range, or you will risk nutrient lockout. How are you testing your ingoing water and solutions?
How are you testing runoff ph?

Quote:

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Originally Posted by Rusty Trichome

So do you still feed with every watering? How much and how often?

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Right now I'm feeding 2/1 (two with Biogrow, one without).
But probably because of the high humidity (?) I only water/feed them every 4 days avrg... So since I created the topic I fed them twice and tommorrow is the first one without fert.

Quote:

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Originally Posted by Rusty Trichome

No, I didn't miss the perlite. And nope, it's not anything like hydro. And I suggest you keep your ph in recommended range, or you will risk nutrient lockout.

How are you testing your ingoing water and solutions?
How are you testing runoff ph?

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I'm testing the ingoing and runnof with a digital PH tester... When the problem started the PH was 6.7 average. Now it´s 6.2 for one and 6.1 for the other.

The burned borders stopped for the new leaves but some of them have the very tip burned, but not spreading to the whole leave.