Help with red spots and yellowing leaves please

Every run during week four of bloom my leaves start to yellow and get red and brown spots all over them and I don’t know how to fix this. Any advice or tips from anybody would be welcome


Can you take a picture in white light? Fill this out too. Thanks, and welcome

  1. Indoor or outdoor? - size of grow?
  2. Otigin of seeds?
  3. Regular, feminized, or autoflower?
  4. Origin of water. PH, EC/TDS of source water?
  5. PH and TDS/EC of if mixed solution?
  6. Grow method? Soil, Soil-less, Coco, Hydro, Aquaponics. Please explain.
  7. Nutrients or fertilizer system used.
  8. What typr of lighting are you using? LED, HID (MH, CMH, HPS), or Fluorescents? Please elaborate.
  9. What are the temps in your growspce? Day / Night?
  10. What is the RH = relative humidity in your growspace? Day / Night?
  11. AC, Humidifier, De-humidifier?
  12. Do you have a Ventilation system? Size? 4", 6"?
  13. Co2 Yes / No?
  14. How long have you been growing?
  15. What budget have you set in order to grow successfully?
  16. If you grow hydro, then please explain your hydro method. DWC, R-DWC, Ebb and Flow, Or;
    Other? Other?
    16b. Size and temperature of solution in reservoir?
  18. Square area under lighting.

Welcome to the forum @PopeMoses it looks like your plant is in flower phase.
We need full spectrum light to access color and symptoms. Also need a full shot of plant and plants.
Try turning on your flash for a good picture.
Looks to be doing well. Possibly signs of potassium and/or magnesium deficiency. Need more info to determine cause and effect.

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Welcome to the community !

Also when leaves are damaged, yellowed or dried out they need to be removed. The dead plant matter has no defense agains microbes. This allows those to spread rapidly throughout the plant. They also block energy from being absorbed for photosynthesis.

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These are just going into week six of flower. All seeds I have used are feminized from ilgm. 5’ x 5’ indoor grow tent with three Mars Hydro 800w LEDs. Grown in ocean forest soil with fox farm trio of nutrients every other watering. Cal Mag used about a teaspoon every few watering’s. I have ventilation going in and coming out. Air conditioner dehumidifier and humidifier if necessary. The pH of the water I put on it is always around 6.0. I don’t really know how to check ppm. The temp during the day is between 72 to 77° and about 65° at night. Humidity stays between 45 and 55%. I’ve been growing about five years But I have only had this problem for the past year or so with different strains. I always get good bud but this seriously affects the yield. I’ve tried trimming the affected leaves off before but I end up having to cut every leaf off of the plant because they all end up with this . I’ve done everything on my own so far with no help and only Internet advice so I’m just at a point where I’m stumped. If anybody needs any more info to go on or if I forgot anything just let me know. I really appreciate you all taking the time to help. Thank you

And also I forgot, yes there is a grow bro CO2 system in the room

So you are running co2, at what levels?
Also some more information would help us out a lot.

The reason we ask for more info is It looks to me you have a few different deficiencies but we don’t know what you are doing and it very well could be from a toxicity, like a calcium toxicity will lock out many minerals, first being potassium.

Could very well be a ph issue, when you push plants to the levels co2 is needed they metabolize at a high rate and weakest link will show. Plant growth is determined by your least abundant mineral.

Beautiful setup man! Thumbs up!

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I’ve been using this for CO2. Just a solution you mix and refill every other week that I got off eBay. Don’t really know how much CO2 it puts out

As far as watering I was using springwater originally bought from Walmart by the gallon but didn’t notice much difference between that and using my tapwater so that’s what I’ve been using for the past few years. Use three cap fulls of the fox farm big bloom and one cap full of the tiger bloom per gallon Every other watering during flower phase. I use about a teaspoon of Cal mag about every fourth watering. I try to keep the pH of the water I’m watering with right around 6.0 but I am using a color tester to test it so I imagine it’s only so accurate. The vents going in and out our 6 inch vents with fans on either end and a carbon filter on the one going out. Any more information you need to know just ask I’m just throwing it up here as I think of it

And the seeds I use are all feminized from ILGM

Does anybody out there have any advice need any more information or anything? These are getting worse by the day so if someone could offer some suggestions that would be great. Please

I would ph higher, around 6.5, are you watering to runoff? Have you checked runoff ph?
What’s your ppm going in?


Have you considered your bloom nutes are causing issues? I had a brand that did not go with my autos (2 different strains, same resevoir) but my ohotos (2 strains, 1 res) liked it just fine. I needed to add cal mag, esp in flower. They got brittle and spotted, added more calmag plus and got em green. They threw 3 leafers and everything. Only autos, only using bloom bases and micros. I have the photos in bloom and using a diff brand and my bfs autos arent doing it either with the diff brand. Using humbolt bloom base and micros flower fuel and calmag rn. But def had toxicities or/and deficiencies related to nutes. N seemed a lil heavy in grow w nutes i was using, too. I balanced it out as best i could 70/30 on part a/b but i wont use them in bloom again. Just something to consider.

I am watering till it runs off and I need to check the pH of that. I don’t know how to check PPM. I bought a digital tester that is supposed to check that and PH but at the risk of sounding like an idiot I can’t figure out how to use the thing so I’m stuck using a color tester for PH and don’t know how to check ppm. These are the same nutrients that I’ve always used and I have successfully grown the strain before without any problems as well as others I’ve tried. It’s like I said just all the sudden the past couple of years this happens with every plant no matter what strain. I tried to grow godfather OG and it was literally the worst weed I have ever grown in my life. Other times come out OK but just don’t have much of a yield. This is just white widow in the pictures it should be a fairly easy grow that I’ve been successful with in the past but just like every other kind I try now the same thing happens.

Any time spots pop up I check 2 things first, PPMS in the Run off, pH of run off/medium.

Your meter should come with instructions on how to use it, but it’s pretty straight forward. The important part is being able to calibrate it, and have a testing solution to test its accuracy so you don’t have to waste calibration fluid. In example… pH 7.0 and pH 4.0 solution. Some meters like bluelab actually use these to calibrate and test accuracy.

It’s the absolute most common problem soil growers face, pH drift, salt build up. Always start here. Even in coco this is where I start. If those numbers are in check you can start looking at deficiencies, pests, light intensity.

Even if there are problems with pH and PPMs you can correct it, but anything already effected will continue to worsen and the leaves effected that don’t look effected will also continue to worsen and show signs/worsen. The healthy ones will be fine. Continue to track these numbers throughout the grow. So you know which leaves are experiencing the after shock.

OK so it turns out my pH tester only tests pH. So I don’t know how to check ppm does anybody know how to do that?

You’d have to get a meter for it. Either on Amazon or a local hydro/garden store.


Are decent meters, no particular order. A lot of people say that the generic/unbranded ones work ok for a time.

Awesome. Will do that right away. Checked the runoff and the PH was at like 5.0 so I’m definitely gonna need to take it up more than I have been when I water and maybe water with more runoff. Any more suggestions are welcome. Thanks for all your help so far as well

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