Just as a trial, go to Apps, Dashboards, create a new dashboard. Deselect use all devices, and pick these two. Then go back to the dashboard tab, go to this newly created dash, and manually add tiles. Re-add the tile using the water template like you did before.
You also could try using the "attribute" template, select one of the attributes in the right column and see if it is different behavior.
Water sensor 6? There is a community driver that you might try: [RELEASE] Aeotec Water Sensor 6 w/ Dock
