Bottled water is one way to increase your stash of emergency hydration. Don’t open the bottles until you are ready to use them,beware that the bottled water, in time, will absorb strange flavor and smell from the things around them. The plastic used is slightly porous, and will allow for certain scents and tastes to seep in. Also- there would definitely be those in the anti-plastic bottle camp ( I think I’ll tent there) who would warn about chemicals from the plastic leeching into the water.
If you are not planning to store the massive quantities of water you will need in very space-wasting, individual bottles, it is a great, not just good idea to use food-grade water storage containers.
If you are recycling containers for your water storage, avoid former milk or juice jugs. They will not be free of bacteria growth while storing water in them.
Glass is cool , but then not-so-cool, because it can easily break. And it’s heavy!