Put the sliced cucumber in a medium bowl (which has a fitted lid).
Combine 1 cup of water, the vinegar, dill, sugar
, garlic, salt, dill, mustard and coriander seeds in a small saucepan
over high heat and bring to a boil. Cook until the sugar and salt is dissolved. Remove from the heat and taste for tartness, add more sugar if too sour
and let cool to room temperature.
Pour the cooled liquid over the cucumbers
, cover and refrigerate for at least 4 hours and up to 48 hours, stirring the mixture at least once.