I think you are over rehabilitating that tree. This is actually worse on the tree in its condition. If you give a blast of fert after a drought to the roots, you could have also added by burning the roots and possibly giving them nutrient lock up. And, soaking once a day is most likely excessive. In its weakened condition, the already finicky roots of a fukien can rot really easily. From almost killing some of my fukiens a couple times when I started growing them, I would say no more fertilizer, and water just before the soil is completely dry. And, make sure its getting nice well circulated air.