In part 3 of How to Select a Water Filter, we’ll finish the sediment filter category by grappling with some of the more difficult sediment issues and by identifying some misunderstood water issues that simply don’t belong to the sediment category. Let’s start by discussing micron rating. A micron is a metric unit of measurement, and is extremely small. There are 25,400 microns in one inch. As it relates to water filters, the smaller the micron number, the smaller the pores in the water filter. Avoid the classic mistake of starting too small. Many people think if five microns is good, one micron is better. That’s not really true. If you begin too tight, your system will suffer from pressure loss due to clogging. Choosing the correct micron rating is entirely about your unique sediment. If you have sand that’s large enough to be visually identified, then you probably don’t need a 1 micron filter. Sand granules are anywhere from 75 to 150 microns, so a 50 micron water filter will be just right to handle your sediment problem. If, however, you have ultra fine sediment that feels slippery to the touch and is so tiny that you are unable to visually identify a single particle, you almost certainly require something much tighter. As a standard rule, begin loose and work down tighter until you get the desired effect. For those installing new systems, purchase multiple cartridges with varying micron ratings so you can experiment and discover what works and what doesn’t. Don’t be scared to experiment! If you own an industry standard size water filter housing you are not locked in to a single variety of water filter cartridge. For complicated reasons outside the scope of this article, one variety of media may perform better than another, so if you’re unhappy with the results of one cartridge, simply try a different one. Even if your water filter performs well, you can always test drive new filters to find better performance.
For difficult sediment issues, you may require multi-stage filtration. This involves multiple water filter housings with lower micron rating water filters in each successive filter stage. This is required in situations where there is a broad range of sediment sizes. Perhaps you own a well that spews both sand (large particle) and silt (small particle), and though it may be possible to accomplish decent filtration with merely one water filter housing, you will have much better results from a two stage system. In some situations the particle size isn’t as obvious, but if you have heavy amounts of sediment in the 5-50 micron range, you may find a single 5 micron cartridge is the best way to obtain the level of quality you desire, but you probably need to change the water filters frequently because of clogging issues. In this situation a dual water filter system with a 25 micron followed by a 5 micron will provide significantly better results. Another circumstance would be water coming from a pond or stream that has large organic matter that could be filtered out with a RUSCO spin down sediment filter followed by a two stage water filter. Each circumstance is unique, but complicated sediment issues can typically be resolved with a multi-stage water filter system.
The sediment category wouldn’t be complete until automatic backwashing sediment filters are discussed. These are systems that are usually 40-50 inches high with a control valve on top of the tank. They look similar to an ordinary water softener. These systems do not use water filter cartridges, and need little maintenance. The precise filter media depends on the brand, but they do basically the same thing. They remove sediment down to a particular micron size, and then they backwash the filter media based on time or total water usage.