So, is it less, or fewer?
When comparing two quantities, it’s not always clear whether it’s better to say that you have less of something, or fewer of it.
The basic rule is, if you can count it as individual items (apples, dogs, bottles, fingers, enemies), use fewer.
If the quantity in question, however, can’t easily be counted in individual units, use less. As in, “You’ve got less time than you think”, “He could have brought less water”.