Mananese deficiency ?

just wondering whats going on with this tiny little Northern lights autoflower. its 5 weeks old and about 4" tall. it was started with 6 other northern lights auto's, all of which are a lot bigger. some as much as 4x the height. the plant seemed to be pretty healthy besides its size so i figured it was just a bad seed. anyway, i noticed the bottom leaves yellowing today and the closest diagnosis i can get is that its deficient in mananese, but it could be magnesium deficiency as biobizz nutrients are lacking in magnesium and i haven't fed it epsom salts yet. very much appreciate some words of wisdom.

Lookin at the cannabis deficiency chart I think ur right....
The top leaves r really dark and The bottom leaves r getting yellow from outside in

Starting to think it's a potassium deficiency now. Seems to fit all of the symptoms associated with it. It's like solving a puzzle, weed is the reward

haha your so right xD totally like a puzzle with sweet sweet rewards.. from the looks of it, it seems to lean towards mag def.. don't forget it could also be locked out too. try testing your run off and compare what is going in and what is coming out.. I say mag def because the way its coming from the outside, not only from the outside but from the sides.. along with the remaining green veins is a good indication of mag.. don't completely rule everything else out, but let us know what you end up doing and how things turn out for the baby. im actually battling mag def because im growing in coco for the first time and I haven't gotten everything dialed in yet.