The spring tails actually live in the soil and help to break down waste. They will eat any mold, fungi, and other unwanted stuff and convert it into food for the plants. Same with the isopods. Any of these workers who venture up to the plants become frog food. The target is to create a sort of mini ecosystem in your vivarium. When you build your substrate layers you start with a false bottom...I used perelite. Then a layer of nylon screen. This gives a permeable barrier for drainage and keeps your soil layer healthy and well drained. A layer of charcoal will purify your drainage water, and ABG substrate gives the plants and micro/macro fauna something to live in. Spagnum and live mosses on that, and some leaf litter to top it off. If set properly, your vivarium won't need to be cleaned for years. My next vivarium will be a bit fancier, I'm incorporating a small waterfall and stream into it. Bromiliads are a plant that are important in the dart frog hobby. The frogs use them for breeding and will deposit hatched tadpoles into the pools of water that collect in the stems where the leaves come out. Pretty cool!