Oxidisation of toxins and destruction of pathogens, good and bad. IMO i would only get one if you had an emmensly large load on your tank, but a U.V. would probably be first stop if you were going this route.
One came with my tank equipment. I hooked it up from the start to my skimmer. I've had pretty stable water conditions. However, I've had a difficult time with certain inverts - can't keep a brittle star at all. In investigating the possibilities, I've found the ozonizer to be a real unknown for me. It doesn't correspond with any of the usual tests I run.
No, just make sure your dosing the correct quantity. Either lower it so that the levels are safe should any accidents happen. Or best yet, link it up to a Redox probe and controller and have the Ozone adjusted to optimize the redox potential in your system. But for now de-tuneing it would help.
