Not sure if nute burn, heat stress, or magnesium deficiency

i just started a full dose for flowering following the GH chart from the bottles which i have been following. i just started noticing some leaves in the pictures below. i thought it might be heat stress but i am seeing it on leaves lower on the plant. it also looks a lot like nute burn and mag deficiency. maybe a combo?

I’m not familiar with General Hydroponics products, but with Fox Farms I know that they say the directions on the bottle are for stand alone applications, for using more then one product you should follow the feeding schedule.

Have you compared the instructions on the bottle to the published feed schedule they have on their web site? I took a look at their web site and they have about 10 feed schedules listed depending on type of hydroponics system and product line.

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I will check it out

Experienced community members and expert staff will be better informed and more capable of providing a more informed answer.

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I have used GH for the past year, year and a half on about 2 dozen plants over a few cycles. Typically start feeding in veg after about 30 days from sprout and using a 1/3rd dose gradually moving up watching for plant changes.

Since all strains are different, I only use a half dose of feed and a half dose of calmag, gradually moving into a full dose as the plant matures. By the time I flip to flower the plants are getting near or full doses of nutrients. Assuming you’re using the GH flora advanced program for soil (drain to waste).

I have started a thread somewhere here on ILGM with a 6 plant nutrient Test which I’ll update later today or tomorrow. Side by side GH vs Humboldts secret. So far after only one feeding the Humboldt plants are noticeably bigger than GH plants in the same space. Same soil, same everything. Based on initial results I’ll likely move over to Humboldts when I run out of GH products in the next few grows.

Not to worry, most of the plant looks healthy. I also think this is a Nute burn and not a deficiency. If things look worse tomorrow than they do today I would flush. Hitting the reset button. Once the pots start to dry out again I’d Start feeding and id dial back the nutrients making sure to only give a half the recommended dose. Using GH In flower I always add a teaspoon of blackstrap molasses for good measure. Not sure how you mix GH, but I’ve noticed that if you mix the day before you plan to feed your ph will go up .5 to 1.0 letting them sit overnight. I mix the day before and ph the water to get to 6.2-6.3. Roughly 24 hours later I’ll throw the ph meters on again and it typically has a ph of 7 or more. So before I feed I make sure to shake that up, test again and ph down to 6.2-6.3.

Keep your temps in ideal ranges. Humidity Levels are more important in flower than in veg. Light appears to be high enough and light burn will be noticeable on the top section of the plant first.

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Thank you for the info. i am getting conflicting info on humidity. where should it be for flower? she’s a blue dream fp from ilgm. She is in a hydro set up with about 8-10 gals circulating. ppm around 1300 ph is 5.9. temps are upper 70’s and humidity is about 50%.

Hey Reverend :wave:

If you really want some thoughts from the community on your issue consider replying to covertgrower. Plenty of experienced heads willing to delve into your potential issues if you take the few minutes to provide them the answers to questions for all to better understand the root cause of the issue.

Based on the info you provided and my limited experience w/ hydroponics is you want your res temps much lower than your current temp and if I’m right this could be the cause of your issues or the staff of them. For my two grows in dwrc I had/needed a water chiller to keep my temps down in the mid to upper 60’s or used a supplement like Hydroguard. My understanding is high water temps hold/retain less oxygen. Could lead to or result in a bacterial issues /pythium.

Warm water holds less dissolved oxygen than cold water because the molecules are moving faster than in cold water and thereby allow oxygen to escape from the water

Using the “quick search” here on ILGM turned up some info. Its a good researching tool from real growers w/ real grow problems and solutions.

I recommend reading this ILGM thread if you find the time.

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thanks for the info. i will definitely check this thread out. i should clarify, my res temps are around 65. the enviromental temps are 70’s. i also realized that the Rh has to be below 50% so i have brought that down with my dehumidifier.

i am going to add some straight water (RO) to see if i can bring down the ppm, it’s a little high so i think that is my issue.

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blue dream FP from ilgm
hydroponic DWC with a 5 gal plastic bucket grow site with 5 gal res.
pH is almost always around 6.0, TDS when i took these pics was about 1450. I have replaced the solution since with current TDS at 1050 PPM
I have it in a 3x4x6 tent with a SF1000 light from spiderfarms
Humidity is around 40% and she is on a 12/12 cycle in the 4th week of flower
ventilation is a 6" 440 CFM fan with 6x18 carbon filter
i have central AC but the room gets fairly warm though i have kept the temps around upper 70’s-low 80’s
I am not using CO2
Using General Hydroponics Flora nutrients following the dose on the bottles along with cal mag and hydroguard. water temps are 65-67 F

Let me know if I missed any info you may need. and thanks for the help. she looks better since dropping the dose.

I think it’s mostly mag. As long as you give them a dosage, they’ll be good. Don’t forget the leaves that are damaged won’t recover.

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oh i should mention i am adding Cal Mag at 5ml/gal. it goes into the solution before the flora micro.

and thank you