small black spots on front and behind the leaf of fukien tea

hy, i bought from shop a fukien tea bonsai 4 days ago . He is near the second window that is 1.5m away from main window and gets indirect light the most time. I ordered a cool light neon (none in stock) to give him more light this winter. Watered 1 time when the soil had a bit of moisture about 2 cm in the ground.

I noticed small black spots on leaf(front and back). some very small spots are only on the back of the leaves. on the pot near the roots i found 2 bugs but I washed them away. I can not identify what are the problems.


I had 4 yellow leaf that I removed from the tree. No leaf has fallen and all leaves with black spots are still green. hope you can help me.

pictures:
leaf start darkening 1
leaf start darkening 2
black spot front leaf1
black spot back leaf1
the spots on the tree
bugs on the pot. i washed them away. is the tree in danger?

thank you

Edit: with the help of a friend i could get closer and take new pictures

pictures:
brown bumps front3
brown bumps front2
black spot front leaf
leaf start darkening 1

The "bugs" appear to be pillbugs. They would not be what were making the black spots. They are essentially harmless.

I would guess that the black spots are cause by one of the sucking insects (stinkbug or one of its relatives such as lacebug, etc. may be the most likely suspect). However, all of these are usually quite large and should be easy to find. Thrips or mites are another possibility.

A hard spray of water through the foliage may be enough to get rid of the culprits. Don't spray the soil.

The yellow leaves most likely are just normal leaf attrition.

I doubt that your plant is getting enough light so far away from the window.

I thank you for your answer. will do that after I get carmona more light.

I am seeing almost the same exact thing.  No bugs to be seen, only black spots, leaf dying, leaf drop.  Took several photos of one particular leaf that is typical of what I have seen this past week.  Plant is indoors, under two 100W LED Daylight bulbs.  Plant is recovering from serious infestation of mealy bugs but strongly suspect that I have something else going on and would like to save this tree.  Tree is isolated from all other plants in the house and no other plants exhibit this problem.









And just to show that there are more than one leaves involved.....

I would listen to Jim and follow his advice. If the hard spray knocks a LOT of leaves off, don't be alarmed- FT can be finicky in the winter. They like a LOT of light. Under weak fluorescent grow lights, I lost most of the leaves in winter. Now with stronger fluorescents, they do much better. More humidity has helped also.