Trying something new

[Havoc2617]

So I am getting ready to start my 3rd batch of mead.
I stopped by a local farmers market to pick up some fresh honey and saw a jar called Elderberry syrup.

Typically when I make a one gallon batch I miss 3lbs 48oz of honey.
In this case I would like to use the 32oz elderberry syrup (non syrup consistency more watery).
I don't know how much honey I should use.
1. Should I do the 32oz of elderberry and 1 jar of honey then finish off with water?
2. Should do the above but with more honey?
3. Should I just make a 2 gallon batch using all the honey and the elderberries?
To answer the question before it is asked the elderberry syrup has a sweetness to it but NOWHERE near the sweetness of straight honey.

 

[madscientist451]

If you want the taste of elderberry, I'd save it for back sweetening. If you want to see what its like fermented, I'd use that bottle in a 1/2 gallon batch with enough honey to reach your desired gravity.