Hydrant module, test assignment. All available hydrants will be in the pool on the left. To narrow the pool use the filter and select the search button. The top arrow will move all of the hydrants over. Or you can move individual hydrants.
In the desktop app, go to the hydrant module, and select "Test Assignment". The left field shows the pool of hydrants. To see only unassigned hydrants, check the "Unassigned only" box, then search. After searching for only unassigned Hydrant Tests ...