Reverse Osmosis Membrane fouling
Most RO systems will reduce water hardness levels for your drinking water, but if your water is hard, it will decrease the life of your membrane significantly. The membrane will form a scale buildup that will reduce pressure and reduce water quality. Since water hardness is a problem throughout the home, it is best to install a water softener with a resin ion exchange for the home. This will remove any staining that you may be experiencing, soften your water throughout your home and protect your RO membrane which is the most expensive part in your reverse osmosis system.
TDS = Total Dissolved Solids
TDS stands for Total Dissolved Solids. Total Dissolved Solids is the total weight of all the dissolved solids which includes the salts, metals, and minerals in a given volume of water. The measurement will be given in parts per million or milligrams per liter. If your RO system is not removing 80% or more of your TDS then your RO membrane should be replaced. When was the last time your membrane was replaced?