Comparison Bio Systems RO-50-SL01 vs Bio Systems RO-50-SL03

The amount of water that the filter is able to pass through itself per unit of time (of course, effectively purified in the process); usually stated in liters per minute. This parameter is largely related to the type (see above): for example, in jugs, the filtration rate usually does not exceed 0.5 L per minute, while for main devices that supply entire apartments, a throughput of tens or even hundreds of liters is required.

Note that it does not always make sense to pursue a high filtration rate. After all, other things being equal, finer cleaning takes more time; accordingly, the faster the filter works, the higher the chance that the quality of such cleaning will be relatively low. And devices that purify water efficiently and quickly usually have an appropriate price. Therefore, it is worth considering the purpose of the filter and, on the basis of this, determine the balance between the filtration speed and its quality when choosing. It is also worth keeping in mind the conditions of use: for example, if you need to filter low-quality tap water for drinking, it is better to sacrifice speed in favor of efficiency.

The highest inlet water temperature at which the filter is able to operate normally. Modern filters are conditionally divided into models for cold and hot water: the operating temperature in the first case does not exceed 40 °C, and in the second it can reach 95 °C. For more information on the importance of matching water temperature and filter characteristics, see "Purpose".

Models of replaceable cartridges for which the filter is designed. Knowing the names of models, it will be much easier for you to find a replacement for an exhausted cartridge. In addition, the options directly named by the manufacturer are fully compatible with the filter and correspond to official specifications, while there is no such guarantee for "non-native" cartridges.

Several names in this paragraph are usually indicated for filters with multi-stage filtration (see "Stages of purification") — a cartridge for each stage.

The size of the cartridge indicates both the overall dimensions of the device and compatibility with non-native accessories from other manufacturers. So cartridges differ in width and height, measured in inches. Among the most common options are 5SL (5"x2.5"), 10SL (10"x2.5"), 20SL (20"x2.5"), 10BB (10"x4.5"), 20BB (20"x4.5").

The diameter of the pipes to which the filter is designed to be connected; indicated only for models with water connection, see "Connection". In plumbing, pipes of standard diameters are usually used, and inches are used for measurement — for example, 0.75", 1", etc. Most filters are equipped with a set of adapters for different pipe diameters, therefore, most likely there will be no connection problems, even if the initial diameters do not match. Nevertheless, it is best to choose a filter that matches your water supply in terms of fitting size — in this case, the connection is more reliable, and compliance with the claimed characteristics will be complete.

The filter has its own pump. This feature is found mainly in two types of filters. The first is reverse osmosis systems (see above): the operation of such filtration requires high pressure, but it is not always achieved at the inlet, and a pump, usually electric, is provided to increase the pressure. The second option is tourist filters (see "Type"), where the pump is designed to draw water from natural reservoirs; they have to be pumped manually.

The presence of a pressure gauge — a device for measuring pressure — in the design of the filter.

This feature is provided mainly in main filters and sink models (see "Type"): it allows you to monitor the pressure in the water supply to which the device is connected. However, the accuracy of the pressure gauge is not very high, but such a device is still quite enough to at least monitor the general condition of the water supply system and detect critical rises and falls in pressure.