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Spots and yellow between veins, calcium?

FluxCherry

Active member
I am back in hydroton ebb flo and out of practice. See attached pics.

RO
2.5ml/g silica blast
Jacks321
.5ml/g mr fulvic
1.7ec
ph 5.5-6.2

RH 50-62%
73-82F
View attachment 18919340


View attachment 18919341
View attachment 18919343
View attachment 18919342 View attachment 18919344
I was thinking calcium deficiency, so I brought the RH down to lower 50%'s and have let the PH drift up to 6.2. New growth not showing tip burn and they've been at this ec for almost a week. I have one plant that is un affected, a cindy cake cross. These are mixed of Trinity, SFV and Sour D.
Off the top of my head. Light stress mostly, acting like light stress and low humidity. possibly Micro nutrient lacking. possibly ph issue.
 

FluxCherry

Active member
i really doubt its leaf spot fungi. i get this all the time. Im in rockwool. try bumping up just your micro nutrients. run some mycorrhiz because it eats the same food as rootrot and other harmful things but helps the exchange of nutrients. if you really feel its fungi. H2O2 is nice. read up on it. its easy.
 

LostTribe

Well-known member
Premium user
i really doubt its leaf spot fungi. i get this all the time. Im in rockwool. try bumping up just your micro nutrients. run some mycorrhiz because it eats the same food as rootrot and other harmful things but helps the exchange of nutrients. if you really feel its fungi. H2O2 is nice. read up on it. its easy.
I am running a sterile rez. 1-2ppm calhypo.
 

acespicoli

Well-known member
Its 79 right now. RH is 45-50.

I scoped the SD's and the spots are brown but not more than one here and there not close together. I do see leaf tips where the interveinal area has chlorosis/necrosis. Any way I normally run a lower RH but its a different setup and it was going slow so thought adding the humidifier would get it moving. I have occasionally had pm on some bases but nothing definitive from the scope. There appeared to be some clear droplets at 100x but its not like the fuzz on the clones. I start Silicone after cloning and it usually goes away. I've sprayed everything with micronized sulfur as a preventative. 1tsp/gal. They look better though after the humidifier off so I turned it down shooting for 50.
After two weeks of running a fan and a daily spray with sulfur... low RH ... did tweak'n the nute feed help?
Were you running calmag prior? What about nute lockout is your feeding balanced.
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CalMag whore some You can really bump up. I have ground egg shell, makes strong stems along with the Si
Try to stay below 50% thats the right RH for molds and fungi to start at 40 not so possible
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On a strain that is resistant
60% RH can give a 15% increase in terpene production but you must have fans great airflow
To avoid losing a large portion to rot super dense potent strains are more prone
Indica vs Sativa issue loose airy sativas breathe better

Hows that Trinity Kush? Have you flowered it before? Nice Structure, Smell, Effect ?
 

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acespicoli

Well-known member

The Importance of Automatic Nutrient & pH Dosing​


Automatic Dosing is an important aspect that all commercial growers should consider for their business.


The main function of an Automatic Nutrient and pH doser is to maintain a consistent EC and pH level in the mixing tank at all times.


When using a recirculating system on a commercial scale there is a large surface area inside the greenhouse covered by crop foliage. The crop continually strips out nutrients and water from the recirculating solution in response to environmental conditions.


On clear, sunny days or on windy days the water consumed by the plants is very high due to the increased rate of transpiration. The water that is removed from the system by the plants is normally replaced automatically via a ball cock valve. The incoming fresh water that enters the hydroponic system typically has a higher pH level (e.g. 7 pH). This has the effect of raising the overall pH level in the mixing tank as well as diluting the nutrient strength in the mixing tank (The EC, CF, or ppm level).


If the pH level is over 6.2 pH (or higher) for a period of time then elements such as Iron and Manganese will drop out of the solution and become unavailable to the plants. This will lead to observable Iron and Manganese deficiencies in the crop.


The pH level in a hydroponic system is like having a set of keys which can open a row of cupboards. Each cupboard holds a different nutrient element. If the correct pH level is maintained around the root zone of the crop (e.g 5.8pH) then all of the cupboards can be opened allowing all of the nutrients to be made available to the plants.


If the pH level is higher than the desired level (e.g 6.8 pH instead of 5.8pH) then only a few cupboards will be able to be opened – the rest will remain locked. This means that the plants are unable to access all of the various elements they require for healthy growth.


The nutrient strength works in a similar way. If the nutrient solution is below the desired nutrient strength for a period of time (i.e 1.2 EC for lettuces) then the plants will not have the full balance of nutrients they require for sustained and healthy growth.


The rate of growth will therefore decrease and there will be no consistent texture to the plants. On some days they will have rigid foliage (from a High EC), on other days they will have soft foliage (from a Lower EC). A consistent EC level is therefore desirable so the plants have all the nutrients available to them in the correct balance.


Should the EC drop too low then there is a risk that any impurities in the solution (e.g sodium) will start to make up a larger proportion of the overall electrical conductivity of the solution. This can limit the uptake of essential elements and result in deficiencies.


An EC level which is too high can have a reverse osmosis effect. Instead of nutrients flowing from the nutrient solution into the plant (i.e. Flowing from a low concentration to a higher concentration), they do the opposite and flow from the plant back into the nutrient solution. This is due to the nutrient solution having a higher concentration that what is inside the plants. This has the effect of stripping the plant of essential elements and makes water uptake very difficult. The plant then collapses.


All of the above-mentioned factors are a continual risk for NFT growers who manually dose large tanks with just a hand held meter. Most growers who manually dose will experience these problems at some stage yet they do not realise how much it has impacted on the quality of their crop until they experience automatic dosing.


Manual dosing is fine for small systems but once the mixing tank size exceeds 1000 litres in a high transpiration area it becomes necessary to look at automation.


An Automatic Dosing System solves the problem in several ways:


  • Incoming water from an automatic ball cock valve dilutes the mixing tank solution. The dosing controller immediately detects that the EC level has dropped and the pH has risen.
  • The controller activates peristaltic pumps or solenoid dosing valves to add A, B & pH stock solutions to the mixing tank at preset intervals. The EC level rises to the desired set point and the pH level drops to the desired set point. Once the EC and pH levels are stable the controller goes on stand by as it continually monitors the solution strength.
  • If the EC and pH setpoints are breached for any period of time beyond a predetermined level then the controller sounds an audible alarm to alert the grower.
  • The EC, pH and Temperature level is clearly displayed with bright LED lights on the face panel of the controller. This allows the grower to clearly see at a glance what the tank solution strength is 24 hours a day.
  • The grower no longer has to manually test and dose their mixing tank multiple times each day.
 
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acespicoli

Well-known member
When the buckets were around and im not using them lately
RDWC was what was interesting...
Cleaning and mixing every other day to me was ok when the time was available.
With th RDWC and a automated dosing and testing unit, prob really enjoy them again

Plants can adapt to missing micro nutrients...
In a closed system like lettuce 28 days and harvest
In cannabis 90 days and changing fresh solution every other day...
It was very labor intensive

test and dose their mixing tank multiple times each day.
How many have time for this as hobby growers?
 

LostTribe

Well-known member
Premium user
The Trinity is the Trinity cutting from the PNW, a pure indica. Where ever she was being kept she's been let out to stretch her legs. They have taken great care of her and she's quite healthy for being nearly 30 years old if not more. Takes a little longer to veg but this one is ahead of the pack.

I increased again yesterday to 2.2-2.3, should know if that is going to help or hurt when I get a looksy.

RH isnt that high and I have not seen anything under the scope regarding the spotting or the other leaf issues. I have not added any Calmag to the jacks. Shouldn't it have enough? I had considered upping it with a slight dose but will see if the increased ec helps. Jacks said the lower ec could be showing Mg or S deficiency.
 

Ca++

Well-known member
The automated pH adjustment, presents a dilemma. Many people march the pH up and down, and we had a thread on this very subject, though tbh I didn't look in. Without control, I set low and it gets high over time. It's out of my hands. I set about 5.4 and it will move to 6 in 24h.
I have full time dosing about to be fitted (maybe in a year or two, after I fix a few other things) and have been thinking I might set the tank fill at a certain time, then dose, then switch off the dosing. But study the data-logs and think about turning the pH doser on again, periodically.

As I say, it's a bit of a dilemma. Let it drift a little, or just hold it steady.

I have pieced it all together for about £200, but still need a good way of keeping the bottles mixed.
 

LostTribe

Well-known member
Premium user
The automated pH adjustment, presents a dilemma. Many people march the pH up and down, and we had a thread on this very subject, though tbh I didn't look in. Without control, I set low and it gets high over time. It's out of my hands. I set about 5.4 and it will move to 6 in 24h.
I have full time dosing about to be fitted (maybe in a year or two, after I fix a few other things) and have been thinking I might set the tank fill at a certain time, then dose, then switch off the dosing. But study the data-logs and think about turning the pH doser on again, periodically.

As I say, it's a bit of a dilemma. Let it drift a little, or just hold it steady.

I have pieced it all together for about £200, but still need a good way of keeping the bottles mixed.
I have done both over the years.

I swear the plants love it when I am away for a few days or even more than a week at times. I adjust by hand and normally just down to 5.7-5.8 but I was staring at that same ph npk chart the other day. I might set to 5.2 for a few days. I am still using potassium silicate so this may be causing the jump. Yes daily to 6 or so. Not usually above 6.1-6.2.

If the increased ec doesnt look to have helped i'll go to 5.2 and see how long it takes to come up and report back.
 

acespicoli

Well-known member
"There is less injury to crops because only the fertilizer solution needs to be changed."
How often is this happening ?
 

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