Fill up the sink high enough to submerge cooking pots, that's most if not all the way there. Edit: I just measured my kitchen sink and pot for this, 17x19 and

Fill up the sink high enough to submerge cooking pots, that's most if not all the way there. Edit: I just measured my kitchen sink and pot for this, 17x19 and 4 inches high = 5.6 gallons. If I go all the way to the sink's overflow at 6.5 inches high, that's 9 gallons.