Part of the reason for aid in fish immunity, is that UV Sterilization is that the UVC irradiation which is contained in the unit will break down oxidizers in the water column that would otherwise lower a fish’ immunity (Redox Balance), this aspect is often missed as many persons use only focus on the germicidal/algacidal properties of UV Sterilizers.
This not only has been proven in controlled tests by gurus in aquarium research such as Carl Strohmeyer, it is easy to demonstrate by adding an oxidizer such as Potassium Permanganate that colors the water and running a level one UV sterilizer against a control aquarium with none (all parameters, bio load, etc. otherwise equal) and noting the considerable speed the Potassium Permanganate is cleared from the aquarium utilizing the UV Sterilizer.
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