dwc overwater?

[Gamberone]

One of my mother plants started dropping pretty bad 2 days ago but I can't understand what is the problem...

The situation in this...
3 month old mother plant in dwc, this plant is in the same system from seed so the system is tested

the system consist in a 16 gallons plastic tank filled at half with res and a 3 watt aerator attached to a 60 cm porous tube to oxygen

Now these are symptoms of over/underwater, but all is as before, the day before yesterday when I saw the dropping of the plant I quickly flushed even if ph and ec was right, and added fresh water and nutrients

The ph was (like it is now) circa 5.5 and the ec was at 1.4, now after the flush i lowered it to 1.1

Also the roots are good, white / light brown because of the flora micro

Then being oxygenation ph and ec at normal values I checked the temperatures.
The room temperature is 70, the water temperature before the flush was 61, now i added a aquarium heater to bring it to 64.
RH in the room is at 65%

So
air pump - working
ph - 5.5 ok
ec - 1.1 ok
temp - 70f ok
wtemp - 64f ok
rh - 65% ok for vegetative state
leaves - nice green ok

I can't work this out, the plant until 3 day ago was perfect, now is close to be dead...








HYDROPONICS/Aero Ponics/Coco/Soiless/

How long has this problem been going on?
-3 days counting today

Are you growing in a PVC grow tent?
-it's a non brand tent, the material seems mylar

What system are you running? (DWC? Ebb flow? Aero? Water Farm? Flood Tables? and so on...)
-DWC

What STRAIN are you growing?
-the church ghs

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

What is the age of your plants?
-3 months

How tall are the plants?
-4 feets

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

What Technique are you using?
-topping

What substrate/medium are you using?(Hydroton, RockWool etc.)
-rockwool and expanded clay

What is the Water temperature?
-61 f before the flush
-64 now

What color are your roots? White? Brown? Are your roots slimy?
-white / light brown

What Nutrient's are you using?
-Ghe flora series 3 parts + epsom salts

What order are you mixing your nutrients? (example: veg nutes 1st, bloom 2nd ect)
-floramicro for fist, then epsom salts, floragro and florabloom at last

What is the TDS/EC/PPM you are using
-before the flush EC 1.4
-now 1.1

What is the pH of the "Tank"?
-5.5

How often are you testing your pH/PPM/EC/TDS?
-usually once a day someday once every two days

Are you sure your calibration is correct on your equipment?
-yes


When was your last feeding change? (ie. grow-bloom-micro-additional)
-never, I started at first with low EC, increasing it as the plants got bigger, always with a ratio of npk 3-2-1

How often do you clean your system: example: Flush out water replace with clean water and nutrients?
-once every 3 weeks or once a month

What size bulb are you using?
-1x 600w MH with reflector

How old is the bulbs you are using?
-got it new 2 month ago

What is the distance to the canopy?
-40 inches, this is a mother plant, i take advantage of the nearby light

What is your RH Factor(Relative Humidity)?
-65% lights on

What is the canopy temperature?
-don't know

What is the Day/Night Temp? (Include flucutaion range)
-lights on 20~22 C° (72~79 F)


What is the current Air Flow? (cfm etc.)
ex 125mm 280 mc/h - 165 cfm
in 100mm 140 mc/h - 80 cfm

Tell us about your ventilation, intake exhaust and when its running and not running ?
exhaust is on 24h
intake is on with the lights, so 18h
ventilation is done with two fan a small one, 9 inches, and one big 17 inches

Is the fan blowing directly at plants?
-the smaller one yes, while the big one is pointed at the space between the lights and the plants

Is your water HARD or SOFT?
-I use 70% RO water + 30% very hard water (EC 1.0) from tap

If using RO,Distilled,mineral water, what is the ppm/EC/TDS without any additives?
-EC 0.05

Has plant been recently pruned, cloned off of or pinched
-i took some clones

Have any pest chemicals been used? If so, What and When?
-no

Are plant's infected with pest's
-I think not

 

[hush]

That doesn't truly look like over or under watering to me. I think it's possible the plants were stressed in another way, like maybe temperature shock or something. OR, there might be a fungal infection. I've seen fungal infections look almost exactly like that. Also, as I type this, I'm remembering a plant that had root pests that looked like this right after being attacked. That's just my initial thoughts based on that first picture. Just in case you haven't considered this.

I'd try cleaning the airstone REALLY good, then I'd change the water, and probably run hygrozyme.

 

[stonedwarrior]

3 Watt aerator for 16 gallons is fuck all...

you want something like http://www.ebay.com.au/itm/Aquarium...636915?pt=AU_Pet_Supplies&hash=item27cfc6cd33

 

[hush]

^ Ha, I missed that little tidbit from before... Yeah, you are definitely NOT aerating the water to the degree it needs to be. And now it all makes sense... things seemed fine until a few days ago because a few days ago was when finally the root mass built up so much that it exceeded the output ability of that rinky dink pump.

You need to aerate the HELL out of a DWC. I mean, it ideally should look like a bubbling cauldron, to be honest. If you've been doing it this way for a long time before now, let me assure you: You've simply been lucky up to now.

 

[Gamberone]

3 Watt aerator for 16 gallons is fuck all...

you want something like http://www.ebay.com.au/itm/Aquarium...636915?pt=AU_Pet_Supplies&hash=item27cfc6cd33

16 gallon is the volume of the tank, but is only less than half full of water, somewhere like 7 gallons


The thesis of oxygen lack don't completely convinces me, because the plant didn't show any sign of oxygen lack and it seems strange that there is a drop so fast, I had oxygen lack in another system and at first the roots became brown and slimy and only then the plant dropped, however I'll take it into account, will buy a second larger pump.

Will investigate also in the pest/fungus hypothesis

 

[willyweed]

bigger pump would be my guess too

 

[RubeGoldberg]

you got pics of the roots?

you've lost all hydraulic pressure in the plant, my guess isn't lack of aeration, but just lack up root ability to uptake.

I've seen dwc buckets with 2 weeks of no aeration still stand more erect than that plant.

 

[ozzieAI]

sorry to see your big girl in such a state...it looks healthy green so i would be looking at the roots as well...hope you can save her...

 

[Gamberone]

closeup of the roots just under the pot, they are brownish but woody not slimy

 

[willyweed]

the roots look great,it must be lack of air surely ? 1 watts per gallon i have been informed !

 

[Gamberone]

the roots look great,it must be lack of air surely ? 1 watts per gallon i have been informed !

since i can't buy a new air pump before next week I added a little water pump in a corner placed half in water and half on the surface, it make a water jet with a lot of bubbles

also i added some h2o2


but again this feels strange, if it was lack of oxygen roots should have already become a bit slimy or brownish


Anyone can elaborate a bit more the "fungal infection" or the "lack of root ability to uptake" hypothesis?

 

[exploziv]

FURARIUM, VERTICILLIUM and PYTHIUM are pathogens that can attack cannabis plants, But they usually show some symptoms on the leaves of the plant before it wilts.

 

[cannibaldudekil]

are you giving it any co2 by any chance? i doubt it but it was worth asking ive seen somthing like that happen when they got to much

 

[STUNKY]

I can't tell 100 percent but in the first pic the base of the stem going in the net pot looks different. I have seen the stem become mushy usually on older mothers. Those big fat roots coming outta the net pot they look like they may be soft.. Grab one and see if it pulls of easy. If it does u need to pull all of them off that r loose. Get rid of all mushy roots or stem mass . Get clones of it and replace.. Sometimes they will recover from this but I would replace the mother or u will see this again.. I am assuming u don't fill the res up to the net pot bottom.. Ideal is usually 1 inch below net. Hope u find the problem man..

 

[Ranger]

there are actually thousands of pathogens that can attack and kill cannabis, in fact when i worked lawn and tree care in my business i used to send samples to the state college extension for identification. when i talked to the state head of plant pathology he informed me that he gets tens of thousands of pathogen ID samples every year and out of them he can only identify 10-20% of them.

moral of the story you could have any number of pathogens attacking your plant and many, even if identifiable, have no cures. i know this is a mother plant but you could risk a long term pathogen in your grows if you keep it, instead of eliminating it.

fire blight is a real bitch to have around and it takes no prisoners. there are many blights that kill very quickly with zero symptom presentation prior.

good luck OP in whatever happens.

 

[Hydro-Soil]

The picture looks exactly like a dwc plant that's not getting enough O2 in the water.

The top section of the roots are rotted because of the lack of O2... I've seen plants recover from this, but only when they were caught by day 2 or so. That plant looks like it will have serious issues recovering. I would trim most of the leaf structure back and trim a bunch of the main root mass off... basically cut down on the amount of O2 it's taking out of the water. Until you get a larger pump, that is.

Stay Safe!