Problems with 2nd DWC grow

mixchemical · Aug 5, 2017

Hi all!

Been running my second DWC grow for about 3 weeks now (vegging) and heading into week 4. Having some issues with 1 plant, droopy leaves which comes and goes in different intervals, can't seem to figure out why.

Some stats about my grow.

Strain : Amnesia Haze
RH: About 60%
Growtent temp: 21-23C (lights on) 19-18C (lights off)
Water temp: 19-22C (trying to keep it below 20C with icepacks but fluctuating around that)
Lights: 380W Led light, running veg mode (blue spectrum) now only, about 75cm from the base of the bucket.
Nutes: Flora trio (micro, bloom and grow) and doseaged to about 420ppm.
Water type : Tapwater (55ppm from the tap)
Light cycle : 18/6
Res change: every 7 days
Fans: 1 oscillating fan running with lights on, exhaust fan running 24/7.
Water level: Just at the bottom of the netpot touches the water.

Alright, think i've covered it all! Anyways, i'm running 3 plants in my tent and there is only 1 that is showing these symptoms. The other 2 are looking fine, leaves up towards the light and no signs of anything bad. The plant with issues has good white roots, the main root (thick one) is not soft or anything but quite firm and looks good, no brown roots or anything of that nature.

Tried turning the RH up to about 70% or down towards 40%, made no difference. The droopyness becomes worse as the lights turn off, but that seems logical in some sense.

Anyways, would be greatfull for any tips to be able to get this plant back on track, looks good with all the colors and it's growing so I feel like its something small and nothing major, still, any help is appreciated!

polishpollack · Aug 6, 2017

You probably right, something small like these plants reduce their metabolic activity after hours of light. 18 on might be a little too much. It's been common among growers to use 18 on or even 24 on during veg but this seems to be rumor that has spread widely over time. You can probably get away with less hours during veg and it would be a good idea to research it. If you switched to 15 on during veg this might be okay. The droopiness is probably just reduced metabolic activity. I'm also wondering if your ppm is a little low. You might try 600 and see what happens.
"Whether you're growing indoors or outdoors, you must make sure your cannabis plants get at least 13 hours of light each day to stay in the vegetative stage. If your plant gets a few long nights, it may start budding before you want.

The plant can receive as much as 24 hours of light a day while in the vegetative stage. Many indoor growers provide 18-24 hours of light a day (known as 18-6 or 24-0 light schedules) during the vegetative stage to encourage faster vegetative growth."
http://www.growweedeasy.com/light-schedules

mixchemical · Aug 6, 2017

Never heard that honestly, seems everybody is growing in veg using 18/6 or 24/0 like you said but i've never heard or read that anybody would contest that it isn't necessary.

Anyways! I've been following the nute guide on growweedeasy.com for the flora trio in dwc and it's been landing on 420 during this change and the last, i've tried upping the nutes on the "trouble plant" to 550ppm so we'll see how it responds.

Any thought on the copper damages on the leaf i've shown? It's increasing very slowly but only on that pair of leaf, no sign anywhere else to be honest.

Thanks for you reply!

Xs121 · Aug 6, 2017

It's also possible you're having a zinc deficiency problem. Are the nodes shorter compared to the other plants?

Symptoms of Zinc deficiency include the following...

-malformed leaves
-necrotic spots on leaves

mixchemical · Aug 6, 2017

Xs121 said:
It's also possible you're having a zinc deficiency problem. Are the nodes shorter compared to the other plants?

Symptoms of Zinc deficiency include the following...

-malformed leaves
-necrotic spots on leaves

Well, not from what I can really tell, they're basically all the same, quite short and bushy. I've had the light quite close (about 60cm from the top of the buckets) which is probably due to their quite short height but i've moved it further up, adding another 16cm to the distance from the buckets so i'm hoping for a bit of stretch on them during the last week of veg.

We'll, the first set of true leaves were a bit "curled" at the edges, nothing like a taco but a bit pointed up rather than outwards.

Nothing necrotic except the copper spots on one leaf, i'm going to let the pH drift up over 6.0 and we'll see how they respond.

In regards to the drooping plant, there's about 3 hours left of "daylight" in the tent and it's started drooping again.

OldMedUser · Aug 6, 2017

Some plants just like to droop and if there are spots on a leaf or two just pinch them off and watch for more to change. If not don't fret about it. A deficiency will show in all leaves of the same class and not just a leaf here or there.

Must be rich to toss out perfectly good nutes every week. I rarely change but once during a whole grow right after stretch is done. Tiny plants like those barely eat anything so there really is no need to change every week. Can always just add a bit more nutes to the rez to maintain or bump up the target ppm.

mixchemical · Aug 7, 2017

OldMedUser said:
Some plants just like to droop and if there are spots on a leaf or two just pinch them off and watch for more to change. If not don't fret about it. A deficiency will show in all leaves of the same class and not just a leaf here or there.

Must be rich to toss out perfectly good nutes every week. I rarely change but once during a whole grow right after stretch is done. Tiny plants like those barely eat anything so there really is no need to change every week. Can always just add a bit more nutes to the rez to maintain or bump up the target ppm.

Yeah, thing is though as with anything that takes time, sucks if you get the chance to prevent something during the start so it doesn't bite you in the ass later.

Wow, really? I've always thought that in a regular dwc, non recirculating, you had to change ever week or so due to that the nutes became bad or the water just became to "crappy". Excuse my non scientific terminology there but you get my point.

mixchemical · Aug 7, 2017

Bumping this up with a new plant, new problems

Just saw this now when I took a closer look, leaves look - well - can't really describe it. Look at the pictures. Can't tell if it's stopped growing, it's noticably smaller than the rest though, by looking at the leaves and not the height.

Have tried to google it and checking out some nute deficiency/excess charts but can't find any.

OldMedUser · Aug 7, 2017

mixchemical said:
Wow, really? I've always thought that in a regular dwc, non recirculating, you had to change ever week or so due to that the nutes became bad or the water just became to "crappy". Excuse my non scientific terminology there but you get my point.

I've run DWC grows from start to crop with no change and they've worked fine. Up to almost 6 months in the same water with a DWC ScroG. I just check ppm and add more nutes as the plants eat them to keep the ppm where I want it and always use good quality RO or distilled water. Now I aim to drain and replace after the stretch is over and use a more bloom oriented mix with lower N and P.

I use AN 3-part at a ratio of 3-2-1, GMB, for most of veg then about a week before flipping add extra Bloom and a half dose of Big Bud and might have the ppm around a 1000/2.0EC or even a bit higher depending on strain and environment. Lower ppm with lower RH and higher temp. Plants will use up to 4X the food during the stretch then drop back to about the same after it's done. I did daily monitoring of the ppm drop over a few grows to keep track of how much the plants ate.

So I save lots of dough by not following instructions that are designed to separate me from my money. Think about it. When plants are small at the beginning they are barely eating anything in a week or even for the first month so you're tossing out almost a fresh batch every week as they've hardly touched it. As long as you have lots of air bubbling in there it keeps it fresh.

If you are using tap water with a fairly high starting ppm then you should change your nutes every time you have added back as much water as your rez holds as the minerals in your water will accumulate and throw everything off. With RO water and the pH Perfect nutes all I do is top up with water every 3 days then check my ppm. If it's dropped I add measured amounts of nutes in the same ratio to bring it back up to my target level.

I worked this all out in the last 16 years of doing about 50 DWC grows. I'm planning on doing a lot of them this winter. Tired of the crappy yields growing in pots.

OldMedUser · Aug 7, 2017

mixchemical said:
Bumping this up with a new plant, new problems

Just saw this now when I took a closer look, leaves look - well - can't really describe it. Look at the pictures. Can't tell if it's stopped growing, it's noticably smaller than the rest though, by looking at the leaves and not the height.

Have tried to google it and checking out some nute deficiency/excess charts but can't find any.

I don't see anything wrong with those leaves. Are all the plants clones from the same mother or seed grown? Sometimes it's just the position in the grow grow room that affects one plants growth and not the others too.

mixchemical · Aug 7, 2017

OldMedUser said:
I don't see anything wrong with those leaves. Are all the plants clones from the same mother or seed grown? Sometimes it's just the position in the grow grow room that affects one plants growth and not the others too.

Grown from seed, no clones. I was mainly thinking about the formation on the leaves and also, might not be too noticable, the inner parts of the leaf is a lighter shade of green than the outside along with the wringly nature of the leaf.

OldMedUser · Aug 7, 2017

Got to expect some variation in seed grown plants even from well established, stable strains.

It doesn't look like the crinkling and that is all over the plant but I can't tell with just a pic or two. Plants often lose a few leaves or have a couple go wonky but if it's not all over and new growth is coming in healthy it's generally nothing to worry about. More problems usually arise from trying to fix something that isn't even broken. It doesn't look like a deficiency of any kind or it would be showing up in all the leaves of the same class. Like all the older fan leaves will start going yellow if N gets too low or tops will start going weird if some micro-nutrients are lacking. A leaf here or there doesn't mean anything. One leaf drooped over another can cause water to form between them and then the lower one usually goes all brown and it looks nasty but really doesn't matter.

mixchemical · Aug 7, 2017

Yeah, true true. Just want to get this grow done as smoothly as possible.

One thing to note, i've bumped up the RH on the humidifiers hydrostat to 60% and according to my hydrometer it's at 70% which I doubt, but the plants are not drooping anymore. Don't think it solved the issue tbh but we'll see in the next few days.

OldMedUser · Aug 7, 2017

Vapor Pressure Deficit is something to be aware of too. I've long had problems with salts buildup in the leaves later in flowering and have tried many things like lowering nute levels and recently just lowering the N after the stretch and tho that helped it gave lower yields. After learning more about how RH affects nutrient and water uptake I'll be doing more to keep my RH up. I'm managing to stay around 60% now but come winter it's hard to stay over 30%. Perfect for very late in flower but no good for most of the plants lives.

Xs121 · Aug 12, 2017

mixchemical said:
Bumping this up with a new plant, new problems

Just saw this now when I took a closer look, leaves look - well - can't really describe it. Look at the pictures. Can't tell if it's stopped growing, it's noticably smaller than the rest though, by looking at the leaves and not the height.

Have tried to google it and checking out some nute deficiency/excess charts but can't find any.
View attachment 3991403 View attachment 3991404 View attachment 3991405

You might want to check bronzing of leaves

im4satori · Aug 12, 2017

OldMedUser said:
Vapor Pressure Deficit is something to be aware of too. I've long had problems with salts buildup in the leaves later in flowering and have tried many things like lowering nute levels and recently just lowering the N after the stretch and tho that helped it gave lower yields. After learning more about how RH affects nutrient and water uptake I'll be doing more to keep my RH up. I'm managing to stay around 60% now but come winter it's hard to stay over 30%. Perfect for very late in flower but no good for most of the plants lives.

View attachment 3991523

http://rollitup.org/t/humidity-and-nutrient-uptake.946062/

im4satori · Aug 12, 2017

flora series 3 part

full strength per gallon

veg option 1 (with calmag)
grow 7.5 mls
micro 5 mls
bloom 2.5 mls
calmag 3mls
Epsom 1/8 tsp (0.5 grams)

veg option 2 (without calmag)
grow 6mls
micro 6mls
bloom 4mls
Epsom 1/8 tsp (0.5 grams)

bloom option 1 (not using kool bloom)
grow 6 mls
micro 3mls
bloom 6mls
calmag 4mls

bloom option 2 (using kool bloom)
grow 2.5 mls
micro 5 mls
bloom 7.5 mls
kool 1mls (up to 2mls in late bloom)
calmag 3mls

bloom option 3
grow 2mls
micro 6mls
bloom 10mls

bloom option 4 (high P)
grow 0mls
micro 7mls
bloom 14mls

for a slightly higher EC/ppm mix it the same with slightly less water
for a slightly lower EC/ppm mix it the same with slightly more water

im4satori · Aug 12, 2017

as for your PPM
keep a daily log
follow these rules when managing your reservoirs

ppm goes up or ph goes down, feed weaker solution
ppm goes down ph goes up, feed stronger solution

Problems with 2nd DWC grow

mixchemical

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polishpollack

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mixchemical

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Xs121

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mixchemical

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OldMedUser

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mixchemical

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mixchemical

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OldMedUser

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OldMedUser

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mixchemical

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OldMedUser

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mixchemical

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OldMedUser

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Xs121

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im4satori

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im4satori

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im4satori

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