Need Information on Cal/Mag Deficiencies When Using Led Lights

Discussion in 'LED and other Lighting' started by BB Boomer, Mar 11, 2017.


    licoricetree Well-Known Member

    Mine have a cal deficiency :(

    theslipperbandit Well-Known Member

    Erm Epsom is Magnesium sulfate not calcium
    Fevs, crocodile og and mr. childs like this.

    theslipperbandit Well-Known Member

    And why did u come off as a smart ass using words like
    Photosynthetic Photon Flux Density (PPFD)instead,fucking stick ur fancy words in ur arse. all the flux does it calculate how much par is being absorbed by the chlorophyll at a given point ,I'm amazed u didn't go into a photon rant but the flux is inferior to to PAR imo once the specs ight ur grand especially in a how much par(photosynthetically active radiation (400nm to 700nm) is bemused my cobx4 is rated for. A 3x3 tent will sort u
    mr. childs likes this.

    rkymtnman Well-Known Member

    i think he means he supplements with calcium nitrate to the Jacks hydro formula cause it is lacking and doesn't use Epsom.
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    TacoMac Well-Known Member

    Anybody that believes an LED light causes a calcium deficiency needs to just stop growing immediately. Go to your local witch doctor and pay them to do it. You'll have as much success.

    The fact is, any calcium deficiency you were going to have started long before you ever changed the lights. It takes time for a plant to suck up all of it. You just happened to change the light towards the end of what was already a problem going on several weeks previous to that.
    mr. childs likes this.
    Los Reefersaurus

    Los Reefersaurus Well-Known Member

    My 2 cent, I've switched over from HPS, and it has been rough. So far had a Mag issue, then the plants drinking more then eating, causing really high run off PPM's, then a flush really hurt the roots. SO now everything is limping along.

    My advice is more mag never hurt anyone
    Be conservative with your EC
    Be very aware how much water is in your pots
    Until you get the hang of it

    CobKits Well-Known Member Rollitup Advertiser

    thinking about this today as were just getting into spring and the young cuts arent doing what they should. they are on the bottom of a tent in the basement and im sure are not at right temp. last time getting them up off the floor and putting the tent on a t-stat controlled fan and they were off and running. i wonder if a lot of the problems people see when switching to LED arent in part as a result of leaf temp issues

    wietefras Well-Known Member

    I have always grown with HPS and after switching over to COBs (same PPFD as before) I have consistently needed to add extra calcium.

    Calcium is taken up passively with the water flowing into the plant. Plants under led light evaporate less and therefore they have more problems taking up calcium. So you can try to increase the evaporation or increase the calcium ratio a little.

    Never had magnesium issues, but it's always safer to add magnesium as well when you add calcium.
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    Jimmyclone42 Well-Known Member

    My switch from hps to cobs has been a learning curve as well.. I believe temps, as was stated earlier, is a big issue.. I bumped my temp up 3-4 degrees C and seen a big improvement..
    Fevs and theslipperbandit like this.

    theslipperbandit Well-Known Member

    False, I've grown the same strains, clones and when I'd my 600w n 400w mh I never got Calmag issues in veg ever, it only occured when I u know why?
    • Calcium and Magnesium deficiency. LED lights usually produce much less heat than a HPS light of comparable productivity. The lower heat levels from and LED means the leaves of a cannabis plant generally transpire (evaporate) less moisture under LED compared to HPS. The transpiration differences mean that Calcium and Magnesium ions can be less mobile under LED and this may cause deficiencies that you will have to correct with nutrient additions. You may not notice this issue in soil which I have.
    • (and many grow nutrients) already contain adequate levels of Calcium and Magnesium. but I always recommend Calmag as they both occur together usually
    Thats why I add endomycorrhizal b4 I pot my veg girls since its a symbiotic relationship she'll source the hard to attain minerals and it also helps with stress and what not.. Heck if it wasn't for mytocorrizal wed never have established plants on land those cunts chilled underwater
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    theslipperbandit Well-Known Member

    That's exactly what it is mate the cobs produce less heat so cal n mag ions can be less mobile. I'd suggest foliar Calmag for a quick hit either when lights out when stomatitis are open to release oxygen or just before lights on.i prefer just as lights out as the plant has time to absorbed .if u need a wetting agent use natural soap no fragrance or any of that crap but tbh I just foliar the underside n once on top near daily...not lashings now but they just been flipped so I m I may up the dose,the plant will tell me... Heck here's a pick I've not deleted yet think it was just before flip noexif_49cc68ee.jpg . now I veggie em under 2 cob 4 at half power 100w and my cobx9 also half but now since I flipped they seem slick n I found if ur girls are getting cold find some sort of Styrofoam to sit em on.
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    theslipperbandit Well-Known Member

    Or go to a pet shop n buy one of those heater mats for reptiles n put ur girls on it

    theslipperbandit Well-Known Member

    I've me sms twin fan speed controller kept at 26 but she barely passes 25c with all lights on but at the start that many cobs produced a fair bit of heat so where I'd usually attach my ducting to the hood like I did with my HPS,I pulled in the ducting secured it away from the cob fans to the middle of the tent n attached a ram 9" off the frame so my shit don't ever heat(grow rooms towards where the sun rises)

    theslipperbandit Well-Known Member

    Ppfd is photosynthetic photon flux density. It's used to see how much par is present at any given point ur aiming for 400nm_700nm and of course it's a good idea to add Calmag n not just cal as they usually Def around the same time,think it's due to the ph range of absorption but try some endomycorrhizal next time it's pricy but insane I'm adding to my compost since I recycle soil

    wietefras Well-Known Member

    @theslipperbandit, I know what PPFD means. That's why I know it's roughly the same now as I had it before with HPS.

    I grow in DWC hydro and mycorrhiza do nothing but die in water. So I stopped using them. They are mostly for making extra phosphor available and do nothing for calcium deficiencies anyway. I don't think Myco's are that pricey either. At least if you buy them from the people who make them, instead of from someone who slaps an expensive label on them after buying them from the people who make them.

    To add calcium, I dissolve some seaweed calcium product with coccoliths and add that to the DWC water. This is a product supposed to be used in the garden. However since I never had calcium deficiencies before, that was the only calcium supplement I had laying around and it worked great and it costs practically nothing. So I kept using that. Helps with buffering the pH as well.

    I don't see any magnesium deficiencies. Only a calcium deficiency (sometimes severe and sometimes hardly visible). So I assume there is already enough magnesium present in the GHE FloraNova nutrients I use.
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    Yodaweed Well-Known Member

    @wietefras it's because LEDs aren't putting out the spectrum your plant needs so it develops a deficiency, no LED is full spectrum, they are either a blue diode sprayed with a phosphor coating or a bunch of colored diodes that are combined to imitate white light, none of them actually produce a true full spectrum light ,they are all targeted spectrum even the white light LEDs.

    If you used blurple leds the problem would be even worse. Blurple LEDs can't even grow lettuce good, the color is terrible for the plants and makes them look ugly and tip burn.

    Plant's developed over billions of years to grow with the sun's spectrum, which is a ball of burning gas. There is no burning gas in an LED diode.

    It's why if you go from a 250w hps to a 1000w hps you wouldn't have the same issue you are having. This problem has nothing to do with light intensity or par or anything it has to do with the crap spectrum LEDs produce. It's the main reason i no longer use my LEDs as a main grow light, they are best used as a supplemental light.

    theslipperbandit Well-Known Member

    It has everything to do with par without par plants can't survive amd my last crop outdid my 600w hps

    theslipperbandit Well-Known Member

    And plants started underwater it was mytocorrizal that found nutrients on land for em so they can survive.

    MrTwist1 Well-Known Member

    BB Boomer

    BB Boomer Member

    Er, besides shooting your mouth off making assumptions maaaybe you should stop growing because with an attitude like that there is obviously nothing to learn from you. I am simply doing research and don't recall putting out the welcome mat for trolls.
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