I don't think star fruit has as much sugar as you think it does. You did not describe how you prepared the star apples, usually cutting up and kind of mashing them, then freezing them in bags to get the ice crystals to break up the cell walls is the easiest way.
Even then 1 lb is only going to provide a few points on the SG for 5 gallons and your primary source of sugar would be the honey.
At 7 lbs your very light at 1.4 lbs/gal. Per hightest's spread sheet these are the normal ranges.
Dry: 2.5 - 3.2 lbs/gal
Sweet: 3.4 - 4.0 lbs/gal
Sack: 4.3 - 5.0 lbs/gal
On the bright side, it will be ready to drink much faster as there are fewer esters to age out.
I hope this helps, I would really recommend reading through the sticky FAQ at the top of this section, it made me realize how little I really knew about meads and yeast.
In Primary: Belgium Chimay clones.
In Secondary: Braggot, pale ale, end of the world white.
Conditioning: Mead, Cider, braggot, Belgium Wheat.
On Tap: Clones, Chimay Blue, Red, Porter, malted cider.
Bottles: Far, far, too many to list.