I'm on a well system, and have a holding tank. Current tank is 15 YO, metal, and is showing signs of it's age. I'm replacing it with a fiberglass tank, and, although I have an old Home boy Depot filter on the main line, the plumber reccommneds a new one. I gotta agree. High iron content, multiplied by the steel tank, is starting to affect toilet bowls, the washer, etc. Hence, my quest. I can't swing for a Culligan system, but I figured something like these might be "doable" http://www.homedepot.com/webapp/wcs...angId;=-1&catalogId=10053&productId=100083450 Water usage is not high. Showers daily, laundry about every day (1 load), dishwasher once a week. No heavy lawn watering. Thoughts?