TL;DR: I found a ficus tree under a water tank, removed it, and placed it in a tray with soil, I'd like to turn it into a bonsai tree. Please advice. Pictures attached.
I recently stumbled upon a bonsai plant under a water tank. It grew with no actual soil, just water that drips from the tank but seems to be very healthy. Green leaves, about a third of an inch trunk, and long roots. I estimate it has a few months, maybe even up to a year due to the width of the trunk? (though I am quite the rook, so I could be totally wrong about this).
Anyway, I decided to remove it from under the tank. The root seemed to come off in one piece for the most part, or otherwise with little loss. And I am debating how to proceed now that I have removed it from there. (I know, I should've come here before removing it).
I love the idea of making a bonsai tree. I know it's a lot of work and I'm be willing to commit to it. However I am not sure how to proceed. I have included some pictures for you to take a look at it and hopefully make some suggestions.
At the moment, I have placed it in a tray with a combination of sand and dirt, keeping the soil humid. I have placed it in a area protected by the wind, with direct sunlight, which resembles the area where it grew.
I'd very much appreciate your advice. Thank you.