deficiency in autoflower

Hello there,

This is my second grow, and first in Coco

I have these 3 plants from Fastbuds, the 2 at the back in Autopot tray, having the same feed from the reservoir but as you can see one of them looks a bit behind with some symptoms that I don't know!

Just to mention I recently flushed both pots in autopot with 5l of ph balanced water and I put it back in autpot.
PH of runoff was 7, and EC was around 1700.
I'm feeding only ph perfect trio from advanced nutrients.


Any help would be appreciated.

Are you hand feeding the one in the front? Because it looks fine.
1700 run off is extreme........probably caused by not having any run off.......salt build up big time.
Consider hand feeding to substantial run off at least once a day and never use plain water........if you have to flush use a weak nute solution.

The nutes solution is at 1700EC so I’m not surprised also the other plant in the autopot looks fine imo, or maybe I’m a newbie let me know?!
the third one that I’m hand feeding actually takes the same exact nutes but I hand feed it myself from same res.

Coco works best in a drain to waste method.
I don't think either plants in the autopots look good.......just my opinion.
There's a reason the hand watering plant looks better.
When you say the EC is 1700......do you mean the ppm's are 1700 or the EC is actually 1.7?

The EC is around 1.7, considering I'm using hard tap water with an EC of 0.7–0.75. I don't add CalMag to the nutrient solution, but I've noticed some pH fluctuations in the reservoir recently, which probably threw things off a bit. This didn't happen in hand fed plant because I was directly adjusting the ph before watering.

some growers advised me with calmag, do you think that could be an issue?

I use tap water and never have to add a calmag supplement.........but that's me.
Why don't you just hand feed all three plants? It's obvious the autopot plants aren't doing as well.