Yellowing continues, is this a Mag. Issue?

Reading some recent posts that resemble mine, those turned out to b Mag. Issues, I nearly just went for the Epsom salt as was suggested for others, but thought I better be made sure. What do you think?

@MattyBear @Covertgrower @dbrn32 @Newbrn @basementstealth @blackthumbbetty


When I zoom in it appears like there are little black dots on the leaves. Am I seeing that right, or is the camera playing tricks on me?


@MattyBear I looked thru my loop earlier and didn’t see anything, other than the brown areas at the tips and a few spots that I believe I caused from misting on the leaves to long prior to lights out

@Okie70 if those are brown spots, that would present as a phosphorus deficiency. It still can be a magnesium deficiency also.
What’s your current nutrient schedule? What kind of nutrients?

Sorry I’m not a hydro guy. I would check ur ph and ppm then make sure your nutrients are deficient in something. Check the contents and %. If ph, ppm and nutes are good. Then idk, maybe temperature or humidity? Again sorry I have no experience with hydro

@Covertgrower just started on Saturday @ 1/4 dose of label, using general hydroponics trio. So this is day 4, ppm tonight at 296, pH 5.9, running nft system, have a couple that look great right next to this one and another that’s not any better

@Okie70 I am a newbie like you and can’t be of much help. One of mine was yellow just on the tips of the first set of leaves. The rapid rooter was wet on top. I soaked up the water and stopped spraying it and it went away. However, I am growing DWC. Someone else with more experience will be able to better identify your issue .
Good luck, I hope you get it straightened out soon.

Are you adding calmag? You need to in hydro

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//[quote=“Okie70, post:6, topic:27181”]
this is day 4, ppm tonight at 296, pH 5.9, running nft system,
NFT is one of the trickiest hydro methods,
everything has to be dialed in to work properly.!

try setting the pH at 6.2 allowing more Cal. intake…???

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I’m not experienced with hydroponics, so I don’t know what the heck I’m talking about lol, but I hear a lot of problems arise from the reservoir temperature being too high. Just throwing that out there as something to look at.


@Okie70 I think your ph is good, but you’ll need to add cal/mag throughout your grow. @peachfuzz can double check my information.

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@MattyBear @Covertgrower @SlowOldGuy @elheffe702 naturally I chose the trickiest method :wink: , I had also added calmag at 1/2 strength 4 days ago, reservoir temp last night was 74,6. My ppm after feeding was 389 and now 296, I expected a larger decrease in 4 days. When should I add again at this point

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@Okie70 the reservoir temp could be lower. Around 65°-68°F it also holds more oxygen at that temp. I’m sure the others tagged will have something to add also.
If you’re already add calmag, then it might be still on the way to recovery.


How long is your pump running for ?
And are you absolutely sure that you checked really good for bugs…?
@MattyBear and @Covertgrower may be onto something…
Is there a rockwhool cube or rapid rooter under that hydrotone?


Pump runs 30 minutes ever 4 hours, yes there is a Rockwood cube which I inspected and it appears clean, roots look nice and white. I did look for bugs, especially after reading your post on spying some bugs out for another grower last night, however I did not find anything using a loupe, this one is starting to show some signs also, and it was my best looking plant!
@peachfuzz @MattyBear @Covertgrower @SlowOldGuy

r u sure u r using NFT, Nutrient Film Technique.?
in a NFT set up the pump usually runs constantly , it creates a small ‘river’ in the bottom of the channel that the roots lay in and r continuously bathed in an oxygen rich nutrient solution,
NFT usually does not have any rockwool in the net pots as it holds too much moisture for a NFT system.!

i think GH Maxi and Flora have plenty of Calcium in them, if u r having a deficiency it is probably due to a root issue, pH, low O2, high root temp, poor quality water…

check this chart, do not go by the pictures on it, they r artist’s drawings, but if u read the descriptions in number order it is a good chart.!

That low of ppm shouldn’t be too much for a plant that size so I would be more inclined to think it’s a problem at the roots. I’m not well versed in NFT so I’m sorry I can’t be of more help with how often to feed using it.

@Okie70 all of your new growth looks pretty good, so I think you’re doing it right. You could bump up the ppm’s and see if she’s just a little hungry.

Here’s a quick read if anyone’s interested:

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This is a great chart, thank you wish I could definitely pick out my issue, several seem similar. For sure a nft system, my roots are not in the water yet, far from it actually, just now some reaching out of the baskets. Thank you

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is this your first run in this NFT system.?

i agree with them looking like several deficiencies,
when we can’t pin point a deficiency it is usually a problem at the root zone,

if the roots r not in the film how r u watering them.?
top feed.???

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