In a blender or food processor add the diced cucumber, honey and the juice from the 4 lemons. Blend until smooth and transfer to a pitcher with the lemon slices, cucumber slices, water and mint. ( Crush the mint a little bit in your hand to help it release its flavors before adding it to the pitcher ) Give it a good stir and adjust seasoning to your taste. Add more honey or lemon if desired then add ice-cubes to the top.
Stir in the chia seeds If using and serve chilled over ice, garnished with mint or basil leaves, lemon and cucumber slices.
Notes
To make this a Cucumber Vodka Lemonade, just add about 1/4 c of good vodka to the mix + more to your taste ;)