HELP! Plants were healthy then took a downturn

[grefranger]

Hey Growers,

On my first grow here. I had some plants there were looking pretty healthy, then after changing a few things they took a sharp downturn, not sure what I did wrong and hoping to get some help here. I looked through the symptoms and solutions pages here and I just don't see anything definitive.

Below here first is a picture of my plants when there were healthy and they looked like this up until about 2 weeks ago when I changed a few things.

My grow setup while they were healthy:
medium: generic potting soil with 30% perlite
light: full spectrum low power LED grow light from walmart, 18 hour light cycle
watering: about every 4 days when the soil got dry, watered with carbon filtered tap water (comes out at about 180ppm), ph'd to about 6.5, watered pots til I saw a little bit of runoff then dumped run off water.
pots: 2.5 gallon plastic pots
plants: photoperiods
nutrients: Dynagrow Gro added to water to about 400ppm with each watering
fans: one small 4 inch fan
grow tent: no ventilation fan but main door was left wide open 24/7.
temperature variance inside tent: 68-75F





Now here are the few things I changed that made them take a sharp downturn, I'm at a loss for what I did wrong here.
2 weeks ago I made the following changes and pictures below of the aftermath, my poor plants!! =(

fans: added 2 Vivo sun oscillating fans running on the lower fan spin speed. they blow directly on the plants.
grow tent: added ventilation fan in the top of the tent with ducting connecting to outside grow tent, pulls air through the bottom of the tent then exhaust out at the top. The grow tent is sealed up except for a 2 x 1 ft opening in the bottom back of the tent. The idea here is I'm trying to get my tent functional without the main door open all the time, as I don't want the plants to get a ton of light from outside the grow tent during their dark hours once I do start flowering later.
light: swapped out the low power led full spectrum grow light to the Viparspectra Reflective series 600W full spectrum grow light. I figured that since the plants are no longer seedlings they could use a stronger light.
Watering and nutrients: no changes!!!!
Plant training: did a little bit of LST bending the main stem to the side.
temperature variance: 68-81F

[herbgrower]

It appears like a nutrient problem; nitrogen deficiency likely could be coupled with more!

[Ziemelblazma]

I had a problem once, I germinated and grew the plant in small tray, Everything was fine, then I replanted in permanent pot and few weeks later plant suddenly started to drop leaves and afflict itself slowly, harvest and quality was terrible.

Later I found out, that roots had grew into new soil which was way too alkaline, and that tortured her.

You did not mention pH in Your post, do You control it? Wrong pH might cause all sorts of problems, And Your plants look like they have more than one problem. On last photo it kind of looks like fungus. but I'd start with checking and regulating pH.

[CaptainWiese91]

PH is 6,5. It’s in the text

[Ziemelblazma]

Sorry, missed that.

[CaptainWiese91]

Shouldn’t be deficiencies when he is feeding it nutrients...
I see a root issue - a severe one.

[ChadWestport]

My guess is that there is a soil Ph issue, which is to root problem here. The secondary problem I see is that with the fans blowing directly on the plants at a rapid pace / short distance that the plants have a lower humidity surrounding the leaf, which causes the stomata to stay open so it can evaporate water. This causes the roots to work extra and pump that water up through the leaves and out. If you have an acidic soil and then it starts flowing freely through the leaves, your leaves will be effected more by the acidic soil than if it didn't have direct airflow and wasn't pumping water out through the stomata at such a high rate.

The drooping looks like it needs water, the coloring and crustiness looks to be from the Ph issue, which can cause nutrient lock out. Adding more nutrients to correct a deficiency will have no effect until the initial Ph problem is addressed.

[CaptainWiese91]

Couldn’t agree more

[grefranger]

Shouldn’t be deficiencies when he is feeding it nutrients...
I see a root issue - a severe one.

Yeah I'm feeding it Dyangro Gro which was recommended in the beginner's guide as a complete nutrient solution for vegetative stage.

My guess is that there is a soil Ph issue, which is to root problem here. The secondary problem I see is that with the fans blowing directly on the plants at a rapid pace / short distance that the plants have a lower humidity surrounding the leaf, which causes the stomata to stay open so it can evaporate water. This causes the roots to work extra and pump that water up through the leaves and out. If you have an acidic soil and then it starts flowing freely through the leaves, your leaves will be effected more by the acidic soil than if it didn't have direct airflow and wasn't pumping water out through the stomata at such a high rate.

The drooping looks like it needs water, the coloring and crustiness looks to be from the Ph issue, which can cause nutrient lock out. Adding more nutrients to correct a deficiency will have no effect until the initial Ph problem is addressed.

Thanks for the more thorough feedback Chad, I have the fans on there because I had a small white powdery mildew problem show up. Would it be good if I took it down to 1 fan and set it higher up in the grow tent further away from the plants?

I don't have a soil PH meter, could I run ph 7 water through the pots and test the runoff to see what the soil PH is?

[grefranger]

Okay I found something

https://www.growweedeasy.com/ph#soil-pH

Soil
Water going in should be 6-7 pH
If runoff pH is…

• 6-7 pH – in the right range, no changes needed.
• Less than 6 – provide next watering at pH 7
• More than 7 – provide next watering at pH 6

Continue this formula with each watering.

[grefranger]

I watered with 6.53 ph water, and the runoff from all the pots came in at 6.6X. Looks like I'm good on the soil PH.

I found this digging into fans and air circulation more https://www.growweedeasy.com/exhaust...-the-grow-area

They say too much air flow on the plants can look like nitrogen toxicity. Looks like what I did wrong was have my fans blowing directly on the plants, as Chad pointed out as well, and I should have my fans above and below the plants.

I will adjust the fans and give it some time, my plants have some recovery to do..... Thanks for the help!

[ChadWestport]

The input to output there seems very unchanged, that is a good thing.

[ChadWestport]

set it higher up in the grow tent further away from the plants?

I don't have a soil PH meter, could I run ph 7 water through the pots and test the runoff to see what the soil PH is?

That is a good idea. Airflow is definitely crucial in the tent, but if you can avoid a steady heavy wind directly on the plants, that is best.

Here is a quick video on how to do a slurry test using your Ph pen in the pictures - https://www.youtube.com/watch?v=GB5HLqmJzVs

[grefranger]

After moving the fan off the plants and giving it some time they recovered! thanks guys. I flipped these into flower a few days ago.

[ChadWestport]

Thanks for the update, always nice to hear how things turned out. Enjoy the grow

[buds73]

I would move that plant at the back left from in front of the fan. Looks to be having same issues as you mentioned above.

[grefranger]

I've been tweaking my nutrients lately so that is why I got some yellowing I think.