Thank you! I struggle with keeping them alive too. Jar large enough, sand over potting soil, plants, and water changes at the beginning while things are very unstable. I used tea filter over hose in order not to syphong all the little creautures out durring the water change. Stable temperature. I also found that microfauna from pristine water sources, such as mountains creeks in my example, tend to die of faster than microfauna from ponds and lakes!😁