Slice the cucumber and onion wafer-thin.
In a colander, toss the cucumber and onion with the salt and let it sit and drain for 20 minutes.
Press the liquid out of the vegetables and rinse well with cold water.
In a medium bowl combine the vinegar, water and natural sweetener and stir well.
Add the cucumber mixture and toss to coat.
Stir in the dill and ginger if desired.