Romaine problems x_x

Romaine problems x_x

Help ;.; I'm growing some Romaine lettuce on a balcony garden (in pots)...I got them as little lettuces and transplanted them, and for a few weeks they were growing beautifully. Now one has died and two more are dying, and yet another is getting brown dry dead spots and edges on some parts of a leaf... The one that died was at the far rear right, the other two that are dying are the two next to it along the rear side. The balcony doesn't have 100% direct sunlight, is the small difference in sunlight between rows enough to kill them? Or is something else the likely culprit? ;.;
Mystery Corner

Mystery Corner

wall.

wall.

Spring here at Last?!?!?!?

Spring here at Last?!?!?!?

Cheap living room A/V equipment storage

Cheap living room A/V equipment storage

Pink walls

Pink walls

my bedroom

my bedroom