If you don't mind a bit of re-fermentation, then you can use either sugar syrup or honey/water - the downside of honey/water is that it can often cause a haze that takes a while to drop out.
You can just use water, you can also use a sugar syrup made from a non-fermentable sugar like lactose.
Hell, if you're gonna age it and want higher alcohol, then you can use vodka though that can reduce body/viscosity.....
Or you can just bottle it (if it's clear) and any part bottle left over is placed in the most suitable/safest place....... your glass