Stumped, over fert? Mg deg? PICS

Hello community could use more minds besides my own.

What type of medium; soil or hydro?-Hydro, 100% Canna Coco
What brand and type of soil?-Canna Coco
Indoors or outdoors?-Indoors
What strain?-Skunk #1 from seed
How old are the plants?-20 days
What type of lights and how many watts?-400w MH
How far from the lights?-15 inches
What is your watering frequency and source of water?-RO water, watering every two days
What, how much and when was it fed? NPK?-First two feedings were just 5.8 RO water. First ferte feeding was 3 ml Rizotonic 2ml Canna Coco A 2ml Canna Coco B 2ml Cal/Mg. ph 5.8(ppm about 250). Next feeding was 400 ppm 3ml rizo 3 ml A 3ml B 3 ml Cal/mg.
Last feeding was yesterday full strength Canna nutes at 900 ppm(Guy at hydro store said to do it)
What is the medium/runoff pH and PPM if in hydro?-400 ppm 5.6
What are the temps and humidity in the room?-75F 40%
What size pots?-1.5 gal
Any bugs? Look real close.-no



Plants looked good but had some weird twisted leaves when they sprouted, but growth was good. After 14 days or so I gave first feeding, 3ml Rizotonic 2ml of each Canna CoCo A + B 2ml Cal/Mg. ph 5.8 ppm 250. Tips on one plant started to burn. Also almost all leaves are curling up like a taco




After that first feeding they started looking yellow so next feed I bumped up everything by 1 ml. After that feeding yellow got worse so I flushed with phed water.




After I flused I went to the hydro store the guy looked me in the eye and promised that you can follow Canna's Coco feed schedule at 100% strenght and be fine. He swore by this.
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So I fed at almost full strenght 900 ppm or so. 24hr later the spots started to occur



but growth looks really good.

FLush?

Please help(P.s. had an accicdent and some leaves got cut off, again accident)

Update, did a flush of the worse plant, the only one with the brown tips, ph was 6.4 ppm was 120. Just yesterday I put 900ppm at 5.8 so she ate. Doesnt seem like too much ppm for her, ph is a little high but I thought mg was absorbed better at a higher ph?

Hey man I think I'm having a similar problem. I have 5 plants going in soil but only having this problem with the one. Check it out lemme know if it looks the same (first picture)

https://www.rollitup.org/marijuana-plant-problems/325007-what-these-brown-dots.html

I know it can't be nute burn because I didn't use any yet. They are only about 2 weeks old. I thought it might be a deficiency too so when I watered them today I fed them with Schultz 10-15-10 at 1/4 strength. I'm preparing them for an outdoor grow and was planning on moving them outside in a week or two. Hope it clears up by them.

BTW- it seems like a lot of ppl, both soil and hydro, have been having this problem at 2-3 week lately.

Hey sonar you look like your in the same boat..I am thinking its thirps..you should look into that. I am going to start treating with neem oil or something similar..

What the heck are thirps? haha

It isn't thrips. Even for hydro, that ph is pretty down there. You might have all the mg you need in the rez, but it can't be accessed by the plant because it's locked from it. raise your ph a little. Here check this out.
https://www.rollitup.org/attachments/general-marijuana-growing/395557d1198364479-charts-charts-more-charts-nutrient_chart.gif

it says that mg starts to be available around a ph of 5.8. raiserup.