Magnesium deficiency or magnesium toxicity

I’m growing one photo ghost train haze from Rare dankness seeds in a 5 gallon pot. After 3 weeks into veg she started have red in the stems very bad, it was everywhere. The new leafs stayed small and growth almost stopped. I checked the runoff PPM and it was in the 5000. I did a heavy flush and had it back down to 146PPM. She was then topped off with nectar of the gods soil #4 and fertilized with Hercules Harvest ph to 6.2 to 6.4 after every two pH waterings. After almost 2 weeks of normal development the leafs started to slow down on growth and the red started coming in on the new leafs and steams. I’ve added calmag to the ph watering and I hope this will work. What do you guys think

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I get the red purple in the stalks all the time. Leaf stems and all leader branches main stalk and all. As long as the plant looks healghy id say its not a bad thing. Depending on the light being ised. Leds can cause the red vein looks in the stalks stems. @Covertgrower gets them also using cob lights

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Yea in using mars hydro 1000w LED and it’s kinda close right now cause I have an auto in the tent almost done. I’ll try to raise the light and cut it down to 75%

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My guess is the heavy flush is going to be followed by additional problems and issues.


The red stems are not a trigger that something is wrong enough to haven given a flush…

It needed a flush because the ppm runoff was over 5000

The soil was way too hot

First I would suggest your plants are looking healthy. Not a cal-mag deficiency in sight. Not sure why the growth slowed, maybe it’s working on roots, or the DLI (daily light interval) isn’t high enough. Your plants are at the point where the DLI needs to be at its highest.

I’m not familiar with the soil you are using, but Fox Farms Ocean Forest, when new from the bag, would have a runoff ppm of around 5000. Having a runoff of 5000 isn’t a problem, knowing that it is 5000 and knowing you need to monitor it until the ppms naturally fall before feeding it is the common procedure.

Heavy flushing where someone is trying to drive their ppm to under 1000 when growing in soil frequently results in additional issues. You will have to monitor your plant(s) and know how to respond if something comes up.

I’ve seen where final flushes suggest flushing to the low hundreds, but even the need for a final flush is coming under question these days as it appears it does more harm then good.


May I suggest you goggle Marijuana deficiencies chart, I just found it and its amazing. It has pictures of all the deficiencies and in different stages. I would say a gamecjager. Cat

Hey there, high ppm’s in the rootzone can contribute to slow or stunted growth. So that may be what’s happening! What type of water are you using and what is the pH of the water runoff? Sometimes when using well or tap water, there can be high levels of sodium and chloride and they can cause salt build up in the rootzone aka high ppm’s! If you are using RO or distilled water, there should be little to no sodium or chloride in your water.

Ppms in water is around 100. I didnt check the ppms in soil before I started this grow but the soil has been reused 2 times, its fox farm. After the flush I add# Mycorrhizal and nectar is the gods soil #4 to help the roots and to feed the plant a little

Gotcha, with only 100 ppm’s your water sounds pretty clean! Mycorrhizae is awesome but I’ve never used nectar of the gods. What fertilizers are you using for veg and flower?