So if I have 3 leaves growing in a pot, and 1 gets root rot, is it possible to save the other 2? And if so, how would this be achieved?
Many root rots are caused by a bacteria which takes hold if poor conditions are present like water logged soil. In a small pot of seedlings which have less resources than an established plant it's likely that if one has root rot the others have
It does no harm to gently separate them into different pots with a free draining soil and good light and see what happens.