A live culture of at least 200 Folsomia candida springtails, supplied in a vented tub. They feed on mould, which helps keep a build tidy.
These springtails are harmless to plants and captive bred. They suit any closed build where mould may appear on the substrate or wood. Open the tub over the build only when you are ready to add the springtails, and keep it stable until then. They are a small, low-fuss addition to a closed or humid build.