Can be trapped but spotlighting works best, can be found in most unpolluted streams.
Tap, stream or rain water, just don't use dechlorinaters (koura are extremely sensitive to them)
Below 20 degrees, can be kept in warmer well oxygenated water, but shortens lifespan and increases chance of infection and parasites.
A Kouras diet is mostly herbivorous, so plenty of veges (boiled for easier consumption) and bugs, heart, shrimp, prawns, pellet food e.t.c