Warm the water in a small saucepan over medium heat. Add the coriander seed, and then stir in the salt until it dissolves completely. Set aside, and let the brine cool to room temperature.
Prepare the beets.
Arrange the beets in a jar, and then drop in the ginger and orange peel. Pour the cooled brine over the beets until covered, allowing 1 inch of headspace in your jar. Discard any remaining brine.
Place a weight over the beets to keep them submerged, and then seal the jar tightly using a fermentation seal or airlock. Allow the beets to ferment at room temperature for 14 days. Transfer to the fridge and enjoy within 6 months.