A: Because, water softeners are poor devices for removing a large amount of iron.
Water softeners are poor devices for removing a large amount of iron (1 PPM and higher). Each part per million of iron will consume 5 grains of water softener capacity where hardness (calcium and/or magnesium) will only consume 1 grain of capacity for 1 grain of hardness. This is great for companies that sell salt, but not great for you because your water softener will use more salt by needing to regenerate more frequent and will be subject to iron fouling. A water test should be conducted every year to determine if your iron problem has gotten worse since the system was installed.
There are several things that could cause you to still be getting iron staining from your water softener.
1. It is critical that your system never run empty of salt.
2. It is important that the time of day be kept correct and that no one uses water between 2 a.m. – 3 a.m. (default regeneration time for most water softeners) when the system is regenerating. While the system is in regeneration, any water used would be unconditioned (coming straight from the well) or you will pull in excess iron that should be going down the drain line.
3. It could be, your resin tank is too small to handle all the iron. A water test will determine if your system is too small or if you would benefit from an Aquatek Pro Aerator.
4. It could be you are not regenerating often enough, or using enough salt per regeneration for the small unit you have or your family has grown and there are more people using more water.
5. It could be that your iron content exceeds the recommended maximum. 1 cu.ft. of resin can effectively remove up to 1 part per million iron without significantly degrading water softener performance.
6. On rare occasions the iron could be coming from just the hot water tank. If it is more than 20 years old it could be rusting out on the inside, thus putting iron back into the water. This is also true in older homes, again over 20 years old, that used galvanized plumbing. Run water out your tap to see if the iron is mostly on the hot side.
Above are the common reasons a working water softener might still be allowing you to get iron staining. For additional help and recommendations, call us at 772-538-0284 and we will assist you in eliminating the iron problem.