If your water contains flakes of rust or sand, or is cloudy, halsey taylor water coolers will help. Inside the screw-on filter housing is a spun polyethylene filter that traps the particles. You can also get two-stage units that include an activated carbon filter for taste/odor improvement. However, if you have dissolved iron, which commonly results in rust stains in the toilet, a filter won't help. You need a water softener or a specialized iron-removal filter (consult a water treatment professional).