Yes! It will depend on the container used and the temperature stored. The larger the volume, the longer the hydrogen will stay in the water. You should fill your container all the way to the top with NO air space. Make sure to close the container tightly. Once you open the container to drink for the first time, it will obviously leave that air space. It’s recommended at that point to try and consume the rest within 2-4 hours.
However, if you are going away and you keep a container filled to the top with no air space, it can last up to 10 days. It’s best to keep chilled in a glass bottle in order to keep the hydrogen the longest.