White crystally "shards" coming from stem onto leaves, PM or other issue?

[ChrisSch]

Hello, this is my first grow and have hit my first issue. Been googling and have had no clear answer to what this may be. They (4 of 5 seeds) germinated in 3 days using paper towel method. Then planted and came out of the soil just a few days later. They have been growing great ever since (as far as I can tell). Went away to work for 2 weeks while wife watered/took care of them. Came home and had to get them into bigger pots, they were close to being root bound. Set up the tent (4x4) on June 6th, have fan going (oscilating tower fan just for air movement, proper fan should be here tomorrow - 4" Vivosun AeroZesh T4), 2 100W LED Full spectrum lights roughly 18" above, humidity around 50% w/ lights on, goes up at night, 55% ish. 25 C lights on, 22 C lights off. This happened 1st night in tent (June 7th morning woke up to this, wasnt there when went to bed), to only 1 of the plants. 3 have zero sign of this. Just wondering what this is/if anyone else has experienced something like this before? Powdery mildew has come up a lot, some have said its normal actually showing great signs of the plants ..I just dont know, want to ask the experts what they think! Moved into 5 gallon grow bags. Seed started in coco coir, then moved into Soil/Coco mix w/ perlite. (Read was ok to mix) Soil is organic herb+veg, Promix brand I do believe. Nutrients Canna Coco A+B, changing to GH since moving to soil (maybe shocked the plant changed mediums?) also adding CalMag. Using GH brand for PH balance keeping 5.5-6.5. 3 Pics are of the plant in question, the last was right after set up, got 2nd light Saturday afternoon as 1 was too tiny.

Since they look like shards of glass, checked to make sure a light didnt pop and they all seem to be fine.

Any advice is much appreciated for this first timer and Thank you in advance!

Strain is Blue Dream

[Wayzee]

Hey Chris, that doesn't look like powdery mildew to me. I think that's more of a outdoor thing as well.
Looks like some of the lining of your tent or something synthetic rather than what a plant would produce. Or is it the cal-mag somehow ?
May I ask where you got your blue dreams from?

[ChrisSch]

Thanks for the reply, good thinking there. Could be something from tent as it was just put up. The CalMag I dissolve right in my watering can, just a few drops of it and mixed no where near the plants.
I got them from a store in Saskatoon, Sask, Can, not from an online store.

[Wayzee]

Ah ok. Oh I noticed you were using Celcius, and thought you might be in Aus haha.

[ChrisSch]

Lol all good!

[DabberDog]

The leaf is otherwise as healthy as the rest of the plant so whatever it is it is not damaging your plant.
Brush it off. See if it comes back. Weird stuff happens that doesn't have explanation.
It is not WPM.

[ChrisSch]

Thanks to you too! Kind of my assumption at this point. Just playing on the cautious side of things and seeing if anyone has seen something like this before lol

[Allenpro]

How do the underside of the leafs look?
I agree I would just brush it off and see if it comes back, what is above the leaf that my drop that

[Allenpro]

Now I see it on a lower leaf that is not directly under it. What do the shards look like under a loop? Not eggs I hope

[Rwise]

Definitely something on it, brush it off but not into the pot. Looks like epsom salts but looks like doesn't ID it.

[Allenpro]

It reminds me of a cal/mag folage feed from Extreme Gardening but good point on not into the pot

[Bluey]

Looks a bit like sand or ground glass.

[dirtymike]

Vermiculite

[ChrisSch]

Morning guys, the undersides all look, same as top sides. Bit of sprinkle onto other leafs. Gently wiped away last night not into pot. The only thing above is the light, and not even directly above. The light may just catch the side of the pot

[Allenpro]

I am hoping its not mites

[ChrisSch]

Closest I can look is zoomed in on camera from phone. Pretty sure it isnt eggs, not like any eggs ive seen before. Nothing on the bottom sides of the leaves either. Wiped off onto damp towel gently and will see if it comes back or anything changes! Thanks for the tips!

[Allenpro]

That may be the end of it then