Move or shake the jars a little as possible. The creatures that live in them should be observed, not disturbed. Add no food. The green plants make their own food, and the animals eat plants, or animals whose food came from plants. Use pond water to replace any water that evaporates.
Tap water containing chlorine is harmful to some creatures.
Tiny water fleas , such as Daphnia and Cyclops, darting through the water. Small shrimp like animals with curved backs and many legs, called scuds, swimming along. Diving beetles carrying their own air supply with them. Caddis larvae pulling their cases along. Mosquito eggs later changing into wigglers hanging from the water surface and later hatching as adults.