possible deficiency? Blue mystic AF

Alright guys this is my Blue mystic AF. Right now she is turning yellow from what appears to be the inside. My best guess is that its a deficiency of either N or Cal/Mg. This is the only plant out of 2 with this problem.. please help her by helping me help her):

Thread of my plants since day one if it helps: https://www.rollitup.org/auto-flowering-strains/732580-x2-blue-mystic-af-grow-4.html#post9682643

what soil u using and lighting ect.....? will help diagnose problem

Maybe your soil is too hot. I killed a bunch of seedlings this year before realizing the common element was the soil and that it was likely too hot.

My bad. I am using cocotek coco coir. 4, 26w CFLs. I fed EXTREMELY low doses of calmag/dynagro bloom. I know bloom isn't meant for veg but people have used it successfully for veg. The dose was 1/8th of eaxh mixed into a gallon which was then poured into a water bottle 3/4 full of clean neutral water.

From what I understand about coco, some brands need to be thoroughly rinsed before using due to salt buildup from sitting in brackish water. I don't know anything about cocotek, but apparently that can be an issue with coco.

Edit: did some quick reading, and it doesn't appear that salt buildup is an issue with cocotek...the only other thought is that maybe you're overfeeding, even though you are using small amounts.

Coco absorbs calcium and magnesium. I always pre charge double dose of cal mag to avoid these issues. I even add 1 tbsp dolomite lime for the long run. Not too hot at very low strength. Cocotek is usually good after 1 rinse. 5.8 PH and calmag should fix good luck. Look into KISS method and go from there. 7 PH is death with coco!!! Have I earned my rep yet?

Did you wash out the coco before using? the PH nice and low?

No nutrients before 5th or 6th level of leaves !!

If you are using a soilless medium without trace elements I would recommend watering with 1/4 strength nutes. Make sure it is 1/4 of what the manufacturer recommends for seedlings. I would only do this once so that the nutes are available when it needs it (seeds don't naturally grow in nutrient free medium, it won't burn at that strength). I will say that you are being a little paranoid, as there is no worry until it consumes the cotyledon.

-Sap

chairroller said:

No nutrients before 5th or 6th level of leaves !!

Click to expand...

So if you plant in good soil they'll die lol. You must grow yellow plants. Maybe you should try dandelions. Still waiting for my rep InnDick lol. I scratched your back now it's your turn. I want to take you under my wing.