Filtering where the water comes into the house is the simplest way to improve it everywhere at once. This Pentair OMNIFilter whole home system installs on your incoming line so showers, laundry and kitchen taps all draw from the same filtered supply, which also helps protect appliances and plumbing from the sediment that wears them down. It is built on the 10-inch standard format, the most widely available cartridge size there is. The clear housing is the feature owners notice most. It lets you see your filter working and helps you determine when to change it, so instead of guessing from a date on the calendar you simply look. Servicing is straightforward too: the valve-in-head cap stays plumbed in place while the sump comes away, and a pressure relief button vents the pressure trapped inside so the housing opens without a fight. The housing wrench and mounting bracket you need are in the box, and it is worth allowing about an inch and a half of clearance below the housing so cartridges drop straight out. The filter itself is sold separately, which lets you customize the unit to your own water, whether that calls for sediment reduction, granular carbon, or a carbon wrap for chlorine taste and odor. The system is for cold water use only. Change the cartridge when you notice a drop in water pressure or a change in water quality.