A few fan leaves on my plants have discoloration. What is this?

[jalapeno]

Mostly, I think these look like healthy plants, but I'm seeing this on a few fan leaves. Any clues?

[Canuck147]

Well, with the limited amount of facts from your grow - one can only guess.
You are growing in soil - not sure if you are giving any nutrients or what your pH balance is, cuz you aren't telling us.
I would say the best clue is the middle picture.
You need CaliMagic - will make your plants so much greener and healthier.

Give us another clue....................

[St.buds]

Looks like ph issue to me

[stevenics]

Without more info, it could be ph problems, problems at the roots, specifically the initial stages of root rot,, or the least likely, leaf septoria. I'm sure you read the gwe plant problems page already but here is some pics, check the ones out I mentioned. http://www.growweedeasy.com/cannabis-symptoms-pictures

[Sammy]

Make sure your pH is correct going in as well as coming out check your runoff can't stress that enough. Cut the odd discolored leaves or Leafs off. Of course more info would be a lot more helpful. ☮️

[Vapo69]

Hey jalapeno , welcome to the forum dude, as the other posts hinted at..........it's really helpful if you can give us as much info about your grow as you can, like what medium you are using, soil or coco?......what nutrients you are using and the temperature and humidity in your tent?........I can see that a couple of your leaves are clawing in the first pic, and your plants are quite a light green, maybe a nitrogen deficiency?.....Happy growing

[jalapeno]

Wow. thanks for all the feedback. Sorry I've not provided enough (any) info.

Here's my setup:
Tent is 2' x 4' x 6' tall
Plants are in 2 gallon cloth pots. 5 sitting on mesh screen supported ~ 1" over the floor of a 2' diameter circular drip pan by short pieces of 3/4" PVC pipe.
Soil is Fox Farms Ocean Forest.
Lighting is Viparspectra Reflector-Series 300W LED Grow Light Full Spectrum

Temperature range in tent about 65 - 85, mostly 70 - 80.
RH Ranges from 40 - 55. Occasionally up to 60 at night if the marine layer moves in, the lights are out, and I haven't turned on the Dehumidifier. i'm careful to keep it ≤60 for veg, and ≤ 55 for bloom. Probably drier once there are buds.


Plants are ACDC clones.
Nutrients are General Orgainics Biothrive Grow, @ 2 tsp./ gal. every other watering. I usually add a quart of ph'd water or nut solution to each plant every 3 - 4 days.
pH of solution has been around 6.8. Run off about the same, when I check it (not every time)

But: Soil pH using an analog probe was above 7, closer to 8.

First thing I did when I saw that, was flush all the plants with pH/d to 6.0 water. That did bring the soil pH down below 7 by a little. My current set up makes it hard to check the run off. Waiting for a part so I can fix that problem. s/b here later today. Using General Organics pH Down in whatever I'm watering with.

Re CalMagic. I can try that, BUT. Water here is very hard. i.e. there's a lot of calcium in it already. If the pH is low enough, shouldn't that be available to the plants? It's only been a couple of days since I started being more aggressive about getting the pH down. Since that may not 'fix' the leaves that are already looking ugly, maybe I should remove them, and see if the remaining ones stay clear.

My experience in maintaining a spa here is that the high alkalinity in the tap water makes it hard to get and keep the pH down. The alkaline minerals just eat up any acid you add. This can take time, so testing the pH. immediately after adding nuts and pH Down, may not get the same result as if I waited awhile. Mixing up my fluids ahead of time might help me get the pH dialed in better. That's going to happen anyway, b/c switching to an automatic watering system (Blumat) that gravity feeds out of a 5 gallon bucket.

Switched lights to 12/12 today, and took off a few bottom branches. Given my small lighting and grow area, seemed like things would get too crowded after the stretch if I waited any longer. Maybe already, but better late than later.

[St.buds]

Try ph at 6 tht what I've always done weather it was soil or coco no issues

[Canuck147]

5 plants in a 2 X 4 tent you are to know what the word 'crowded' means soon enough. Double up on your light - I think I have the same one and it's good for 2 X 2.
Any air circulation, other than the dehumidifier?

[jalapeno]

I'm just using half the tent trying for 'sea of green' approach with 5 smaller plants. At least that's the intent. I may have waited a week longer than optimal before switching the lighting schedule. The dehumidifier is in the other half of the tent, though it's seldom really needed as it turns out. Does keep the temperature up bit on the cooler nights we're having now.

I have a nominal 100 CFM 'duct fan' I think also Viparspectra brand. It's exhausting through 4" flexible vent hose to the outside via an unused furnace chimney. A flap at the bottom, opposite side is opened to allow fresh air in. The open flap is below the plants, into a 2" wide space between the tent and a blank wall relatively dark room, so I don't think much light leaks into the tent during the 12 hour dark period.

There's also a small oscillating desk fan. I had to turn off the oscillation feature because even on low, when it aimed itself right at the plants, they looked like they were in a gale. Now it's angled at a wall of the tent which deflects and diffuses the breeze, so that the plants are just subtly 'vibrating'.

Both fans are on 24 x 7.

[Johnhenry]

Don't need to ph General Organics. Read the bottle it should say. I used GO nutes for a few years, your ph should drop to around 4.8-5,1 with nutes . your return should be 6,3 6,5 . Ph your flush water. GL

[jalapeno]

You probably don't have the hard water we have here in Soquel, CA. Tap water pH is about 8, and alkalinity at least 240ppm. Simply adding nute's does bring it down, but not to the 6 - 7 range recommended for soil grows.

[jalapeno]

Not mentioned in my prior response, there's also a 100 CFM exhaust blower, and a small desk fan running 24/7.

The discoloration on the leaf surfaces vanished after I started watering with 6.- 6.1 rather than 6.8 - 6.9 pH. However, there are still downward pointing 'claws' on some fan leaves. I need to saturate the soil before installing my Blumats, so will definitely check the runoff at that point.

Switched to 12/12 lighting, and GO Biothrive Bloom on 10/30.

Comparing this photo to the one I posted a week ago when I started this thread, seems like whatever else may be wrong, they are at least growing vigorously.