These are the basic things one should consider while getting a water purifier. But there are a lot of factors you should be aware of. For more details read this water purifier buying guide.

The capacity: The first thing to see is the quantity of water to be treated and available for drinking. There are portable systems of one or two liters but if you want to benefit from a water reserve for the whole family, you have to start with at least 4 liters of water.

The filtration system: This is what will provide you with pure water. For optimal use, prefer carbon filters with water filtered by gravity. It is quite slow but does not require energy to provide you with pure water. It is therefore a system that will provide water without the need for energy. Note that this is only possible with fresh water and therefore impossible to place salted seawater in this type of filter. A system that can be a very good complement to the water still.

The material of the product: This is an important point since the water causes a chemical reaction on the metal, it is essential to have a stainless steel tank so as not to see your container producing rust. Care should be taken to check the quality of the stainless steel to have a food container without risk of corrosion.