These are photos of the mud and head drums of a 35,000lb per hour Combustion Engineering water tube boiler prior to the installation of the Bon Aqua system. There is obviously a significant amount of scale deposit build-up in both the drum and  tube.

The same boiler pictured below one year after the installation of the Bon Aqua water treatment system. The pre-existing scale has been dissolved away. The stack temperature readings are an average of 25° less than readings obtained in prior years.