All COB Users - Lettuce Grow Challenge!!

i have found vinegar/citric to be unstable for any amount of time..areyou sure you do not mean phosphoric acid?

ANC said:

Sounds like you guys are growing the most expensive lettuce in the world.

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Is there a world record for smallest most exensive pepper?


Don't mind the aphids, they'll be dealt with today.

Still having some deficiency issues, was using 7.5ml of floranova bloom with 3 grams of epsom salts and 6 ml calmag. Changed a week ago to 10ML of FN, 2 grams epsom and 9ml calmag but it doesnt seem to have helped much. Shes drinking a gallon/day right now and still growing fast... Any suggestions appreciated, not sure if I should increase mag or calmag or both. I added a 100w LED from the side/bottom because I wasnt getting enough penetration with the top only lights. Shes getting about 310w of nice cob light right now.

Here is what is going on on the lower/older 'fan' leaves. Starting to get some necrotic spots between the veins also and this is moving more towards the new growth, not just a few leaves anymore.Seems to be happening worse where the light intensity is the highest and airflow isnt an issue at all, I have a small box fan blowing toward her constantly.

thetr33man said:

Here is what is going on on the lower/older 'fan' leaves. Starting to get some necrotic spots between the veins also and this is moving more towards the new growth, not just a few leaves anymore.Seems to be happening worse where the light intensity is the highest and airflow isnt an issue at all, I have a small box fan blowing toward her constantly.
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I have never had to chase a problem like that on tomato's but if I were to guess with aa few minutes of research I would say you are battling Nitrogen deficiency along with a mega dose of Mag deficiency (mg demand due to led's)
Most all of these bottle ferts are week when compared to the commercial powders they typically use to grow tomato's
Try this:
15ml Cal-Mag
7.5ml Flora Nova Bloom
1 gram Epsom Salt

Here's some good info:
http://www.haifa-group.com/knowledge_center/crop_guides/tomato/plant_nutrition/nutrient_deficiency_symptoms/#{A4E97D29-7746-4CCA-B67D-14A77A97A826}

imaybe mg by the look but yes there are so many other ways to achieve this colour

the calvand mag is use both have nitrogen..maybe some more nitrogen

and the ph isn't too high and you do know about pre charging the coco?

.. you do not seem to have lenses/reflectors..which have been my cob prob until i figured ot out

OneHitDone said:

I have never had to chase a problem like that on tomato's but if I were to guess with aa few minutes of research I would say you are battling Nitrogen deficiency along with a mega dose of Mag deficiency (mg demand due to led's)
Most all of these bottle ferts are week when compared to the commercial powders they typically use to grow tomato's
Try this:
15ml Cal-Mag
7.5ml Flora Nova Bloom
1 gram Epsom Salt

Here's some good info:
http://www.haifa-group.com/knowledge_center/crop_guides/tomato/plant_nutrition/nutrient_deficiency_symptoms/#{A4E97D29-7746-4CCA-B67D-14A77A97A826}

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Wait, just realized you are using Magi-cal or whatever with the super low nitrogen so my suggestion is not going to help your nitrogen situation enough.
You really should be using Flora Nova Grow and I think these problems would disappear

or forget those too expensive products and buy some cal nit and mg nit..

i got 35 lb bags for the cost of a coupe of those anemic 500 ml watered down jugs..

the plants love it..

Ive got 25lb bags of Jacks hydro and calnit but I havent had much luck with it, seems like PH tends to bounce around more when I try to use it and my plants never seem happy at all. I could add a few grams of calnit to the FN solution maybe?

thetr33man said:

Ive got 25lb bags of Jacks hydro and calnit but I havent had much luck with it, seems like PH tends to bounce around more when I try to use it and my plants never seem happy at all. I could add a few grams of calnit to the FN solution maybe?

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Try this:
2g Cal Nitrate
2g Epsom
5ml Flora Nova Bloom

I hear you about ph stability. I get that bottles are high priced but "All Nutrients are NOT the Same".
Flora Nova and Ionic in particular are much more PH stable in a recirculating system that products like Jacks, Hydro-Gardens, etc.

I forgot what your source water issue was (hard as hell?)
That may be throwing a monkey wrench in things.
Possibly could do well with just the Nova Bloom and Magnesium Nitrate

OneHitDone said:

I forgot what your source water issue was (hard as hell?)
That may be throwing a monkey wrench in things.
Possibly could do well with just the Nova Bloom and Magnesium Nitrate

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Not sure how accurate this is, it says 480ppm but my TDS meter shows pretty consistently around 320ppm...

thetr33man said:

Not sure how accurate this is, it says 480ppm but my TDS meter shows pretty consistently around 320ppm...
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Probably gonna need to deal with that water
Here is some good info:

if you guys are interested in an RO system for you grow area, this is a pretty good option, it is a little more expensive then a under sink one.

https://www.freshwatersystems.com/p-6853-axeon-hf5-4040-2500-gpd-ro-membrane-element.aspx

then you need a housing for it. They are about $100. you just connect this to a hose and you have RO water. It will do about 25000 gallons at least, probably a hell of a lot more because you are using clean tap water.

you will also need to hook up a valve to the waste side of it to create back pressure. All in you are at about $400, but you will have RO water for the rest of your life in your grow room.

Things to note, if you get 100 gallons of ro water expect to waste 300-400 gallons of water to get it. It will run about 1 gallon a minute, so for me, it will take 2 hours to fill my res

OneHitDone said:

I would say you are battling Nitrogen deficiency along with a mega dose of Mag deficiency (mg demand due to led's)

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Woa, could you talk about the LED and Mg connection?

yep mg[nit] was not mentioned..

and photophoric acid and ro water will

stop swings unless your roots are dying

with Ro you needless phosphoric to ph adjust

I started melting snow today. Will give it a shot with more pure water and see how that goes... Thanks for the info and tips!

thetr33man said:

I started melting snow today. Will give it a shot with more pure water and see how that goes... Thanks for the info and tips!

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that's an option. I am curious of the the PPM of melted snow. can you get a reading on that for us? Then I wonder if its the same everywhere or if it is lower or higher depending on geographical location.

I don't have COBs, but:

In the late summer/early fall I had been growing several types of loose leaf lettuce -5 or 6- under 5k EB strips on shelving. It was all edible, not leathery or thick, but then I harvested it as it was slightly starting to "rosette" & I knew it was heading downhill from there.

My red oak leaf-type got some slight tip burn and it was also not as tender as the rest hile I really enjoyed 'little gem' baby romaine. It also managed to stay very fresh in the fridge for close to a week, washed and spritzed with distilled water.

I also grew cilantro, and lots. The first time I didn't pinch it and leaf mass was minimal. Second crop I pinched it once, once the first set of 'frondy' leaves was out. 3× the vegetation probably.

I didn't have any way to measure light intensity at that point and I found dealing with such dry winter air a pain. I'm moving soon, and far. So I packed my trial rigging up and will resume in April. Lettuce is really cheap right now, the same price as summer?

I'll be setting up something more productive, controlled and much larger after my move. Hopefully growing something worth posting pictures of

muleface said:

that's an option. I am curious of the the PPM of melted snow. can you get a reading on that for us? Then I wonder if its the same everywhere or if it is lower or higher depending on geographical location.

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Well I would think air pollution would play a huge part in the PPM in precipitation. For instance in Canada we have had acid rain that has scorched massive amounts of forest in the north, caused by air pollution

I'm curious whether rain or snow traps more particulates...quite possibly the clouds are the actual filters.

I live fairly close to the western shores of the Rocky Mtns @51-ishN, however it's been a relatively dry winter in my part. Next time it snows I'll go on a mission and report back w/PPM...it's been really windy lately tho and the snow has shit like pine needles all over it right now. Also I burn so much wood heating my house in winter i would assume there's soot all over the place.
Same with my asshole neighbours

& One Love to All

muleface said:

that's an option. I am curious of the the PPM of melted snow. can you get a reading on that for us? Then I wonder if its the same everywhere or if it is lower or higher depending on geographical location.

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Updated plant pic, added a banana cuz tomatoes werent ripening, seems to have done the trick, they are starting to turn on the lower branches now.