Coco ebb & flow overwatering or N deficiency?

Hey guys,

So I know pretty much everyone will tell me I should not have transplanted from soil to coco but I did anyway. It looks like some of my plants are recovering from their transplant shock and I'm starting to see some new growth while others are still really droopy. I do notice my plants new growth is very light lime green and I'm concerned this is either over watering or a nitrogen deficiency. Here is what I got:

GH cocotek A/B
GH rapid roots
GH floralicious
Watering: twice a day for 30 minutes when lights are on
PH6.0
PPM: 1000

Could this be overwatering? The medium dries up after a while and does not stay soaked very long, or am I a little low on my nutes?

You shouldn't have to water with that frequency as small as those are for the size of the pots they are in. I only feed my coir plants every other day when first up-potting. Let the coir dry out a little and once the roots get established then you can do multiple daily feedings if you need. I only feed my plants in coir 450 ppm (0.9ec) in veg with a single daily feeding.

Thanks for the reply. Do you handwater or use a flood table like I do. Does that make a difference in terms of water frequency?

Bump

Van Heineken said:

Thanks for the reply. Do you handwater or use a flood table like I do. Does that make a difference in terms of water frequency?

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I'm back to hand watering now, and I don't use smart pots anymore either. I found I go through roughly 1/3 more nutrient solution when I ran smart pots over hard plastic pots because of evaporation. This also had a tendency to cause more of a nutrient build up in the coir.
Never tried flood and drain with coir and I guess it would depend on how well the coir absorbs the solution during the floods.

Looks like you have a Magnesium deficiency going. Did you educate your self on growing in Coco and the calcium issues it poses? http://blog.botanicare.com/calcium-magnesium-and-coco/

I'm aware of Growing in coco there is a need to add a Calcium /Magnesium supplement but in using Cocotek A/B That contains 5% Ca and 1% Mg according to the label I was under the assumption no Cal/Mag was needed ?

Van Heineken said:

I'm aware of Growing in coco there is a need to add a Calcium /Magnesium supplement but in using Cocotek A/B That contains 5% Ca and 1% Mg according to the label I was under the assumption no Cal/Mag was needed ?

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Is your set up drain to waste or recirculating?

coreywebster said:

Is your set up drain to waste or recirculating?

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Recirculating Ebb N Flow

Van Heineken said:

Recirculating Ebb N Flow

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Right, there's a chance I might be wrong, but the idea of recirculating nutrients when using coco sounds dangerous.

Reason been coco as well as having tendencies to hold on to calcium also contains high levels of potassium and sulphur,
even after its been well buffered it still has lots of K in it, which is why coco specific nutrients contain less K than non coco nutrients.
So when you water your coco what comes out of the medium is different from what went in, your ppm/EC will be higher, I know mine is. Considerably higher. So by recirculating your nutrients your feeding them a set of elements which will change drastically each pass through your pots.
Unlike something like hydroton which is inert and wont change your nutrient mix, your ec would go down and you could top up as required, with coco your EC may go up, it may go down, but you don't know the ratios remain correct by taking ec reading.

here's a link of what top brand canna coco contains even after been buffered properly.

https://manicbotanix.com/coco-substrate-and-hydroponics/

Now have a look here

https://www.alchimiaweb.com/blogen/deficiency-excess-of-potassium-cannabis/

Specifically at potassium toxicity and the resulting lockouts such as calcium magnesium, zinc ect.

I was not a fan of the coco-tek when I tried it. I have better luck with just using plain hydro nutes now, no snake oils and only a little PK boosts.

coreywebster said:

Now have a look here

https://www.alchimiaweb.com/blogen/deficiency-excess-of-potassium-cannabis/

Specifically at potassium toxicity and the resulting lockouts such as calcium magnesium, zinc ect.

Click to expand...

One of the reason I disliked the coco=tek, saw problem with potassium excess when I ran it.

coreywebster said:

Right, there's a chance I might be wrong, but the idea of recirculating nutrients when using coco sounds dangerous.

Reason been coco as well as having tendencies to hold on to calcium also contains high levels of potassium and sulphur,
even after its been well buffered it still has lots of K in it, which is why coco specific nutrients contain less K than non coco nutrients.
So when you water your coco what comes out of the medium is different from what went in, your ppm/EC will be higher, I know mine is. Considerably higher. So by recirculating your nutrients your feeding them a set of elements which will change drastically each pass through your pots.
Unlike something like hydroton which is inert and wont change your nutrient mix, your ec would go down and you could top up as required, with coco your EC may go up, it may go down, but you don't know the ratios remain correct by taking ec reading.

here's a link of what top brand canna coco contains even after been buffered

Click to expand...

What you are saying makes sense but my issue here is that I have a setup of two 55 gal totes as reservoirs and to convert this to a drain to waste system seems expensive. My fault of course for not researching growing coco in a res better, but what can I do ?

I have a drain in the basement but it would see a huge PIA with my current setup to convert over to a drain to waste.

Maybe I'm wrong

Van Heineken said:

What you are saying makes sense but my issue here is that I have a setup of two 55 gal totes as reservoirs and to convert this to a drain to waste system seems expensive. My fault of course for not researching growing coco in a res better, but what can I do ?

I have a drain in the basement but it would see a huge PIA with my current setup to convert over to a drain to waste.

Maybe I'm wrong

Click to expand...

Once you get your skills down in coco you will find that you really don't need to feed to run-off every time if your nutrient profile gets dialed in. It's really all dependent on what you are trying to achieve with running coir.
Shouldn't be hard to switch over, just put a fitting on your fill line and tee off that to some emitters or drippers and a fitting from your drain to floor drain or a separate rez.

boilingoil hit the nail on the head there.
You have two res, use one to feed and the other to collect waste. Switch to a dripper and timer system. Still using what you have now just tweaking it. Instead of flooding your dripping, instead of recirculating your allowing the drain to DTW and removing, maybe set up a small pump to empty that res into your real drain every few days.
Less than $20 to tweak your system without damaging anything you have. Then if you want to go back to flood and drain just buy some hydroton(clay pebbles) next grow.
I love my coco. It suits me perfect. But I have done ebb and flow which isn't much different to flood and drain, amazing systems with the right medium.

thanks so much guys,

I think what I'll look at doing is running an 1/2 hose through my inlet on the 3x6 tray connecting a shut off valve and a tee splitter. From there run two 1/2" feeder hoses and connecting a several smaller lines to drip each pot. The only thing I will have to do after that is run my 3/4 drain hose directly into one of two reservoirs.

Seems simple enough.

Do you still recommend using cal mag to supplement the cocotek?

5% cal should be enough. The1% mag would be my concern. I would look at upping that ratio first. Then I would look at lowering your feed strength as a whole.
Here is some shots of my garden in flower running 550 ppm.

Update:

So I took everyone's advice and upgraded my Coco Ebb & Flow setup to a top feed drip setup. The drip emitters are the ones that drip 1/2 GAL per hour so I don't really have to worry about how much water each pot is getting. I stopped watering for about 5 days and let the roots settle. Once I started watering again with the drip system within days I saw a huge improvement in growth. It worked!

Now I seem to be having another issue. Please look at the pictures. To me its seem that I having a calium lockout due to the high amount of P that the coco medium lets go, yet holds onto the CAL/MAG. Here is some information about the grow for the last 2 weeks:

Strain: WW, NL, Cheese, Green Crack, Jack Herrer, Blue Berry
55 GAL res changed weekly to about 30 GALS. Watering 3 times a day for 5 minutes during lights on
Nutes: Cocotek A/B 6.75 ML/G , GH Floricious 0.7ML/G, Age old Kelp 0.625 ML/G, Maxicrop 0.5 ML/G, Epsom Salt (0.2 TSP/G), Gypsum (0.2 TSP/G)
PH: 5.8-6.4 (mostly around 6.0) TEMP: 64 at night - 82 during lights on. Humidity 61%

I am using tap water which I got tested at the following:
PPM: 271
Sodium: 41 PPM
Potassium: 2 PPM
Magnesium: 19 PPM
Calcium: 19 PPM
Total Hardness: 127 PPM

I'm running at about a total of 850PPM - 271 water = 550-600 PPM Range.

I have considered everything, Nitrogen, Potassium, Phosphate, Calcium I am out of answers. Anyone that can give me some insight would be very very helpful.


THanks!

VH

i hated coco. felt like i was fighting with it the whole grow. finally decided that my medium wasn't going to give me headaches and went to a different medium.

i agree with @boilingoil . i would try a different nute regimen.
have you ever heard of H3AD's formula for coco? it's what i used and was pretty simple. GH micro, bloom and epsom salts.

is RO water an option? would elliminate your water as a potential problem source too