Sugar water does not go bad in the same way that other foods do, because it does not contain any organic matter that can spoil. However, sugar water can become contaminated with bacteria or other microorganisms over time, especially if it is not stored properly. It is best to use sugar water as soon as it is made and to discard any unused portions. If you need to store sugar water for later use, keep it in a clean, airtight container in the refrigerator and use it within a few days to be safe. It is also a good idea to label the container with the date it was made to keep track of how long it has been stored.