I don't know if yours is broken, it sounds like you need a more accurate scale. In water it will read 1 (specific gravity), with water and sugar (un-fermented cider) it will read more than 1. water with alcohol (cider) it will read close to 1.
On a liquid gravitometer water is 1, so oil is about .6 to .8 (lighter than water)
On a gas gravitometer air is 1, so propane for example is about 1.5 (heavier than air)
Guess what I do for a living