Whatever you do, don’t drop an invisible plastic washer, which won’t stay on spigot before assembly. My seat cushion ate one until I found it. 
Perhaps hose washer would work but I prefer the real thing. Cats’ dish remains below and I can tap at will. Gallon jug at sink fills it nicely once a day. Twenty cup dispenser remains by sink and coffee maker. Both are wonderful, sometimes filled from brita pitchers. Catmandan