Hi all, I rescued a ficus bonsai from the bin at my local m&s, it was out of its pot when I found it. I scooped up as much soil as I could. Once home I repotted it with 3/4's of the original soil and some seeding soil. Submerged it in Luke warm water for a about 30 seconds. It's been on my window for two days and the leaves have curled and browned. I sliced a little bit into the bark and it's still green. There is one branch with what looks like new growth sprouting. Can anyone help me revive this little guy or am I fighting a losing battle. I've included some pictures, first two are two days ago thursday and last two are ones taken today saturday

It's not surprising that it's losing leaves if you found it in that state, plus the added disturbance of being re-potted & moved. As long as it has the occasional watering (avoid overwatering, make sure it has good drainage) & a decent light cycle there's a good chance for recovery; ficus also enjoy higher humidity although it's not absolutely necessary unless trying to grow aerial roots.. a humidity tray is good. Typically after defoliating the tree will take a few weeks to months to fully regrow; although with my ficus I've felt like its growth factor is slower compared to others --- but that may also be due to the relative conditions (e.g humidity).

~

Thanks so much I'll leave it and see how it goes.

trees often do not respond well to being moved... Ficus more so some than others, because tropical regions have less variance in their weather patters than places closer to the poles, and ficus is a tropical plant. how many hours of direct sunlight light does it get in that window? Is there a heater right under the window?these could also be reasons that it is having problems.
Water when the soil feels dry, do not submerge the pot in water unless the tree got very, very dry.. and water normally, like you would any housplant.
repotting it, especially with root pruning is not a good idea with an unhealthy tree (unless it's not being repotted when it should have been is causing problems).
Try and give it proper care and see what happens:
www.bonsaiempire.com/tree-species/ficus

I have found that once the leaves start to curl and wilt like that, it is difficult to save that leaf so it might be better to defoliate and hope that the focus responds by putting out new growth. Be cautious because sometimes, smaller branches on a ficus can easily die. You could also consider pruning the branches back a bit so the ficus will have less tissue to worry about, helping the overall growth.