Ozone Generators
Ozone generators are another of the advanced forms of water purification that were originally developed for use in public aquariums and that have now been modified for use by home aquarists. Ozone is an unstable form of oxygen, created by energizing air with an electrical current. This process takes place in a machine known as an ozonizer. The extra oxygen atom that ozone contains separates from the ozone molecule and oxidizes microorganisms, thereby killing them. It also breaks down a large number of organic compounds that are routinely found in aquarium water.
The use of an ozone generator might be seen as a safety measure, but not as a requirement, unless you maintain large numbers of aquariums and frequently introduce new specimens. They are, however, a fairly standard item in commercial aquariums and are quite useful to fish wholesalers and importers. In both of these situations, the constant influx of new animals greatly increases the likelihood of the introduction of pathogens and parasites.
Ozone gas is highly toxic to fish and invertebrates. Water leaving an ozone generator must be passed through activated carbon before it is returned to the aquarium. The specifics of this process will depend upon a number of factors, so the manufacturer's guidelines should be strictly followed.
The effectiveness of ozone in destroying so many types of microorganisms and pathogens is offset by the fact that it is a dangerous gas to use. Ozone is only recommended for serious, adult aquarists with a great deal of experience. Always be sure to follow the manufacturer's directions carefully and seek the advice of seasoned professionals when handling ozone. The gas is also quite destructive to many of the materials that are used in home aquarium, such as plastic and rubber, so be sure to plan for this when installing an ozone generator.
