wiriwiri said:Your plant "appears" healthy...Remember that leaves do naturally turn yellow as they mature, age and prepare to fall off. An occasional yellowing of leaves is nothing to be concerned about. If you do notice your plants leaves yellowing rapidly and en masse then I would worry.
Give your plants the "once over" look under the leaves for s&s of bugs etc,use a mirror as they like to hide on the backside.
I don't know how large a container that is,if anything maybe an upgrade to the next size?
Otherwise don't loose any sleep over it.Happy Growing.