Gavita 1650e LEDs - constant deficiencies

[diseasedmind]

Looks good in veg and first 2 weeks in flowering, then nightmare begins

Dwc
Tap water .04 ec
A/N sensi a and b 1.6-1.8 ec
Ph 5.9 - 6.2
Temp 80 degrees
Humidity 50%

Tried higher temp and Humidity, but ended up with mold.

Is the solution just add boatloads of calmag? Never had issues with hps.
Leds are touching ceiling. Usually about 25-30 inches off canopy before stretch.
Do I need a dimmer?

Any help would be appreciated

 

[Creeperpark]

I'm surprised you are using tap water with DWC. That's why I don't use tap water. It's very hard to match the buffering capacity when using tap water because of the unknown properties.. The problem above is caused by inadequate buffering capacity. If you use RO water and cal mag you can gauge the buffering capacity much better to the point when using LEDs.

 

[Ca++]

I can't remember the thread title.. It was about K in dwc. Uni grow, that looked okay. Table of feed EC, and rise over the week. It's of interest, as your EC looks a bit low. You might not want to chase an individual correction, but instead, just pump up the lot.


ec0.4 or 0.04?

 

[diseasedmind]

I was considering r/o but my setup requires a lot of water. It's just so bizarre that with hps everything looks great, and even in veg with the tap water.

.4 sorry typo on that. Yeah I was thinking of just pumping the base right up, but don't you think that would be to much N in flower. Can the vpd of the room really cause this big of a problem?

 

[Ca++]

The N requirement in flower is generally higher than people think. It's the number 1 requirement for decent sized buds. I don't know your feeds numbers, but I doubt it's high enough in reality. If all is well, you could want 160ppm and I doubt you are over 120ppm with most feeds.

If you were to go RO and calmag, the N gain people get is often overlooked. It's somewhere closer to the amount of Ca than Mg calmag usually gives. My post-it note has fell off my monitor somewhere, but I have found LED grows need more N, and people are meeting this demand without actually realising they are.

You have a few plants. Foliar one with something unrealistic, and see which way it swings.


Edit: Your pH seems high for hydro. Nitric acid might be of use. I know high pH favours N uptake, but quite a few metals won't be happy at 6.2 on hydro. Your meters calibration might not be perfect to, and 6.3 seems crazy in hydro. I think the mid 5s would be a better idea. Myself, I run low 5s. I have a similar tap EC and getting some acid in there is useful (N-acid generally)

180-200ppm N is a common uni research target. A dwc specific run decided on 160ppm. I have seen no recent study as low as our base feeds give us. Which is more like 80-120. It is a base, to add to. A single ml of calmag per liter could give you 30ppm of N. That's not a recomendation, but an example of the N people are really running.

 

[St. Phatty]

I tried using Screw in LED's.

In Veg. they do OK.

In flowering, they Kill Plants.

Amazing what effect the wrong spectrum of light has !

 

[Creeperpark]

I tried using Screw in LED's.

In Veg. they do OK.

In flowering, they Kill Plants.

Amazing what effect the wrong spectrum of light has !

Most errors are caused by the grower and not the lighting.

 

[GF-Z]

The N requirement in flower is generally higher than people think. It's the number 1 requirement for decent sized buds. I don't know your feeds numbers, but I doubt it's high enough in reality. If all is well, you could want 160ppm and I doubt you are over 120ppm with most feeds.

I run into N defficiency with canna BIO, tried everything, but plants finished pale as hell. But smoke was tasty without curing it.. Sadly had emergency and took them way too early... But bud size was a joke, popcorns are bigger... Now trying to compensate N with worm castings and veg nutes during first week of flowering... Will see how it goes

 

[Ca++]

I run into N defficiency with canna BIO, tried everything, but plants finished pale as hell. But smoke was tasty without curing it.. Sadly had emergency and took them way too early... But bud size was a joke, popcorns are bigger... Now trying to compensate N with worm castings and veg nutes during first week of flowering... Will see how it goes

As a bio feed, it's worth checking the N types in it. There is usually a proportion of the N, that's not available until it's gone through some conversion. This doesn't strike me as useful, when you are feeding reactively. Studies have show that in hydro you want no more than 5% of it, and while upto 30% can be done in soil, by 50%.... so is your yield.

You really just want NO3, but if you use it alone, they take on a lot of water. So 5% NH4 is common. I wouldn't try working with anything much higher, if you are running your plants hard. It's the time constraint I don't like. Though with forward planning, it certainly can work.

Most calmag bottles are offering about 5% CaO or 3.5% Ca, along with 3% N that is usually kept to the small-print. So if the bio offers no Ca (like the non bio terra) you can (and perhaps should) give it about 50ppm Ca and 40ppm N, using 1.5ml per Liter. Watch in later bloom, where Ca use drops, and so accumulation could effect K uptake.


Or.. maybe in preaching to the choir

 

[GF-Z]

As a bio feed, it's worth checking the N types in it. There is usually a proportion of the N, that's not available until it's gone through some conversion. This doesn't strike me as useful, when you are feeding reactively. Studies have show that in hydro you want no more than 5% of it, and while upto 30% can be done in soil, by 50%.... so is your yield.

You really just want NO3, but if you use it alone, they take on a lot of water. So 5% NH4 is common. I wouldn't try working with anything much higher, if you are running your plants hard. It's the time constraint I don't like. Though with forward planning, it certainly can work.

Most calmag bottles are offering about 5% CaO or 3.5% Ca, along with 3% N that is usually kept to the small-print. So if the bio offers no Ca (like the non bio terra) you can (and perhaps should) give it about 50ppm Ca and 40ppm N, using 1.5ml per Liter. Watch in later bloom, where Ca use drops, and so accumulation could effect K uptake.


Or.. maybe in preaching to the choir

Just figured out your nickname... Haha good one, I am always tripping in between dependencies of nutrients, thats a hardcore part of chemistry in plant biology.
What about hard water, PH around 7.81-7.90~, can't tell ppm.. Is it logical to add a tiny bit of espom salt with every watering ? Because water is full of chalk, it is everywhere in home...
As I run full bio, thought that making ph down to 6.0->6.2->6.5->6.8->6.5->6.2 and etc. would help a bit with hard water locking out everything ?
Was living in very soft nice, perfect for cannabis water area, now came back to homeland and water here is HARD... Need to adjust a bit

 

[GF-Z]

Looks good in veg and first 2 weeks in flowering, then nightmare begins

Dwc
Tap water .04 ec
A/N sensi a and b 1.6-1.8 ec
Ph 5.9 - 6.2
Temp 80 degrees
Humidity 50%

Tried higher temp and Humidity, but ended up with mold.

Is the solution just add boatloads of calmag? Never had issues with hps.
Leds are touching ceiling. Usually about 25-30 inches off canopy before stretch.
Do I need a dimmer?

Any help would be appreciated

As far as I see from picture:
Obvious vein chlorosis - magnesium lockout/defficieny/whatever?
Burned tips - hard to tell, 2 options: too much or ph/ec ?
Almost all stems are red, plant cant uptake phosphorus. Also they look very woody like, not medium soft, thats sign for ?
I would flush everything, just to save whats left, but this can kill plants too...
Feel sorry for you, but I see a lot of defiencies in 1 plant... I would not go futher than 1.0 - 1.2 EC at this point and see whats happening...
Or maybe try PH down to 5.5, maybe its long term zinc defficieny. By old charts of PH availability i see, that zinc is best available at very low PH range (5.0-5.5)
Giving PH drift from 5.5 to 6.0 works for some people (as far as I heard from old hydro growers in NL)

 

[zachrockbadenof]

i grow in soil with hps/cmh's , never had any plant problem's, i switched to a mars 8000fce in a 5x5tent , and had the same leaf problem u pictured ... some guys said it was cal/mag, others said check the ph...etc...etc... there is def a learning curve with led's... with hps/cmh's , drop the seed into the soil and watch em grow....

 

[TanzanianMagic]

Looks good in veg and first 2 weeks in flowering, then nightmare begins

Dwc
Tap water .04 ec
A/N sensi a and b 1.6-1.8 ec
Ph 5.9 - 6.2
Temp 80 degrees
Humidity 50%

Tried higher temp and Humidity, but ended up with mold.

Is the solution just add boatloads of calmag? Never had issues with hps.
Leds are touching ceiling. Usually about 25-30 inches off canopy before stretch.
Do I need a dimmer?

Any help would be appreciated

It looks very much like phosphorus deficiency. The curled up leaf, the patterns that almost look like infection or the shotgun pattern of calcium deficiency, except that the damage is progressive from the lower leaves up - a mobile nutrient deficiency, which limits it to N, P, K and Mg.

Looking closer at AN Sensi a and b, they have very little phosphorus in them.

NPK

Sensi A = 3-0-0
Sensi B = 1-2-4

An immediate solution would be to switch to 2 parts B and 1 part A.

Also, I agree with using more Nitrogen and Sulfur during the flowering itself.

 

[WingzHauser]

Not hydro. But here's the average analysis of multiple popular inputs when considering Led spectrum.

Everyone confuses dark curled leaves for N toxicity. It's phosphorus deficiency. Everyone tries to fix with calmag. Ignores trace minerals but imports useless rice rot microbes and silica dusts. Uses tons of untapped ksul for flower. Cannabis won't use sulfur without N or K without P. Or really anything without Mn B Fe etc

 

[Ca++]

Just figured out your nickname... Haha good one, I am always tripping in between dependencies of nutrients, thats a hardcore part of chemistry in plant biology.
What about hard water, PH around 7.81-7.90~, can't tell ppm.. Is it logical to add a tiny bit of espom salt with every watering ? Because water is full of chalk, it is everywhere in home...
As I run full bio, thought that making ph down to 6.0->6.2->6.5->6.8->6.5->6.2 and etc. would help a bit with hard water locking out everything ?
Was living in very soft nice, perfect for cannabis water area, now came back to homeland and water here is HARD... Need to adjust a bit

I have 280ppm Ca from the tap, and have poor growth unless under pH6. It's not like they look damaged. They are just slow. While most people are talking 5.8-6.4 depending on substrate, I'm below 6 in everything, and won't even raise an eyebrow if a fresh tank says 5.2
The very professional Bugbee runs everything over 6, telling us cannabis will find it's iron no matter what. However, I feel totally the opposite, and see iron problems in my grows over 6, and see other people have iron problems at times.
Just maybe, my high Ca tap, requires a high dose of pH down, to act upon the carbonate. Removing it from solution, and making the Ca more easily available.
Even with my 280ppm, in soils where I shouldn't need Ca in the feed, I always need some. That tap Ca isn't very available, unless the acid gets to work on it. This all adds up to a convincing reason why hard water users could want to lower pH, rather than let the Ca just accumulate.

I always use nitric, unless it's special circumstances. Such as rooting cuts. Nitric gives us more N, but roots like P, so I use phosphoric (if I have some)

 

[mcattak]

DWC nightmare always begins week 3 of flower......always assumed it had something to do with plant taking focus away from root development

 

[Ca++]

OP

There is a difference in camera's, but you can imagine the timeline the OPs leaf went along. It's there in the first pic from my library. From becoming too dark, to the spots along the veins. Then the un-uniform spots, before the tip starts to curl as the center rusts out. If it's not P, I will resign (and come back with a new username)

If you only lower P in solution, the signs are different. You get the darkening, then the tip (and perhaps sides) may discolour, before rolling upwards. Where here, we also see the rust. Making the answer a bit more involved, than just adding P.

I wonder if this is actually excess salts at the roots.
Edit: DWC though.. and it's been going on a while. The 2nd OP pic shows stalks with stripes of stress or Mg. A general lick of foliage, and green. It could be they just want feeding. I really don't know at this point.

 

[diseasedmind]

Finally switched to RO, think it might have been something with my tap water. Things are starting to look much better. Thanks everyone for the help and input.

 

[Creeperpark]

Finally switched to RO, think it might have been something with my tap water. Things are starting to look much better. Thanks everyone for the help and input.

You did it friend, good for you and you won't be sorry because RO grows the best gardens.