Tardigrades typically can be found near lichens and moss. However they could also live on dunes, beaches and marine or fresh water sediments.
Tardigrades eat plant cells, algae or small invertebrates. Most Tardigrades are phytophagous(plant eaters) or bacteriophagous(bacteria eaters). Only some are predatory.
Tardigrades are invertebrates because they have an exoskeleton.
Tardigrades can survive in extreme environments including temperatures just above -273 C, pressures 6x the pressure of the deepest trench in the ocean. Tardigrades can survive in space for at least a year. They can survive for 10 years without food or water.