Are you in the market for purchasing a portable water storage tank? If so, it will help to know what your options are so you can purchase the tank that best meets your needs.
55-gallon barrels are a serious option for water storage due to how large they are. However, they are not that portable once they are filled up. You can add a dolly to the bottom of the barrel to help move them around if necessary, but you are not going to be easily lifting them if they are completely filled. You'll need to purchase a hose or pump to help you with extracting the water as well. However, they are going to hold the most water at the most affordable price per gallon when it comes to the container.
Stackable 50-Gallon Drums
A popular option for water storage is the stackable 50-gallon drum. While this tank typically costs more than the 55-gallon barrel and holds a little less water, the main advantage is that it can be stacked on top of other 50-gallon drums. This makes it incredibly easy to store the drums on top of each other without buying additional hardware. The drums also have a spigot on the bottom of the drum that makes it easy to get the water out of the drums when necessary.
The nice thing about waterfull barrels is that you can rotate out the water supply with new rainwater. All you need to do is connect a hose to the waterfull barrel so you can use it outside to water your lawn or garden. That then frees up room in the waterfull barrel to collect new rainwater. These barrels are not too heavy where you can still move them, even if you have to tilt them on their side to roll them.
Many people decide to use water bricks because of how portable they are. The small form factor allows them to easily be stacked, and they are light enough where a single person can move them to a new location. The bricks are small enough where they can fit in many places, such as in a closet or underneath a bed, and allow you to have your emergency water nearby so that you don't have to go too far to get it.
The downfall of a water brick is that there is no spigot attached to them, which makes it difficult to get the water out when you need it. You'll need to purchase a pump or pour the water into another container.