I've had a Chinese elm bonsai for over a month now, it's 7 years old I was told. I have been sure not to water on a schedule, and prune the tree about every week or two at the moment, using fertiliser with the water once a week.

When I watered a couple of days ago, I noticed a total of 3 small white bugs come to the surface and go back below it. Unfortunately as there were so few I got no photos. They had a motion almost like swimming, and were maybe a couple of mm long, just like tiny threads. I also noticed some white on the trunk and the moss. The latter went after watering, but now the moss appears lighter in some places. Otherwise, the tree is healthy with no issues on the leaves themselves that I can see. I have looked online and on this forum but no descriptions satisfy my description exactly. Any help would be much appreciated.

It looks healthy.
Small white wormlike creatures in the soil could be fungus gnats larvae, small worms, other kind of larvae, or nothing at all to worry about.
That's why pictures help here.

Thank you Clicio, managed to get a video of one of them. Apologies for the weird lighting/zoom; I had the hold the phone while my other half shone a torch as it was night-time and the kitchen lighting wasn't enough. Best idea of it towards the end of the video; can see its movement.

The „There you are...“ was scary... :blink:

From the video I think you have some dwarf isopods (search the term for a picture, maybe you can identify). I use a tropical species (Trichorhina tomentosa) as part of a cleaning crew on the bioactive terrariums. They feasting on decaying biological material. Usefulness...

/If you find springtails, your soil is too wet and could have excess fungal growth. With those watch out, cause they would eat the good fungi and sometimes chewing a bit on roots also.../

Unfortunately, with just the naked eye, it's really difficult to see them in any useful amount of detail. At the moment they just look like tiny threads to me, and I only see them when I water/feed, so I'm keeping an eye on my tree generally. Thank you any further ideas would be much appreciated.

red.squirrel wrote: Unfortunately, with just the naked eye, it's really difficult to see them in any useful amount of detail. At the moment they just look like tiny threads to me, and I only see them when I water/feed, so I'm keeping an eye on my tree generally. Thank you any further ideas would be much appreciated.

Water a bit less, allow the soil to dry (but do not let it dry out)

I've been trying not to water too much anyway. As an update, in the past week or so the moss has started to lighten, also the pot has some white substance along the edges. Not sure if any of this is to do with the weird weather at the moment (in the UK and it's been variable between very hot and overcast with rain). I am keeping it as an indoor plant, and have just bought a mister to keep it fresh. It still seems happy and is growing very well, still pruning regularly.

The white stuff is scale, calcium carbonates. The result of using hard water.

Why dont you put it outside? Plants really should by outside.