If your source water has a high level of hardness you also need water softener, usually with TDS higher than 700 PPM. Hard water can reduce the lifespan of whole house water filter cartridges. The harder the water, the greater amount of scale buildup occurs, and the sooner the filters get clogged. To determine which product best suits your needs, it is recommended that you get a professional water test done prior to purchase to identify the main issue of your source water.
Note: Water Softeners and whole house systems usually do not lower the TDS level of the water. An additional Reverse Osmosis system may be necessary for your drinking water.