The best solution to an iron bacteria problem is a chlorination/retention/filtration system. Contact a local water treatment professional or two and get their recommendations. Much like any other mechanical system, guarantess only apply to the equipment itself against defects in materials or workmanship. Some companies offer Performance guarantgees but are few and far between. The chlorine will kill the bacteria and precipitate the iron and the dead bodies in the retention tank. A filter then follows to remove any particulate that gets out of the retention tank. The retention tank must have a blowdown valve on it to remove the sediment as needed. Most times a carbon filter is used on a drinking water faucet to remove the chlorine. During the installation of the systems the well and all house plumbing should be disinfected with chlorine. These bacteria are not harmful but are a definite nuisance.