Unidentified bugs

likely spring tails. when zooming in I see their little anti and such. not to bad. they eat dead things and make frass or insect poop and that feeds the plants. When their numbers get up in the medium they start to be found in the runoff when you water. Feel free to toss this runoff into the compost or garden outside. springtails are benfishional bugs for your garden. If you don't like them almost any generalized pesticide works on them. I think BTi works well and I know nematodes works on em. They don't cause the plant any hard. Sometimes the worm castings I use have these little guys in it. Its almost always from the store they don' get aorund much otherwise.