There is a growing awareness of the need to eliminate such pathogens by disinfecting the water in the aquaculture systems [4, 5]. Disinfection is an effective treatment for many types of pathogenic microorganisms, including viruses, bacteria, fungi and protozoan parasites [6]. However, water disinfection

remains a scientific and technical challenge [7]. The most commonly used techniques for water disinfection are chlorination, membrane filtration and ozone treatment [8] but antibiotics and biocides have also been used. Unfortunately all have disadvantages, particularly in relation to the generation of toxic by-products which may cause health risks to human consumers [9]. Additionally, some viral vaccines see more selleck chemicals have been developed in the past two decades, but these are limited to selected viral pathogens and they are also extremely costly to produce and to administer [10]. Solar radiation is an alternative, low-cost, effective technology for water disinfection [11]. Solar disinfection

normally refers to exposure of contaminated water to natural sunlight for a sufficient length of time to reduce the number of pathogenic microbes below the infective dose [5, 12]. So far the most commonly employed method for solar disinfection is to expose contaminated drinking water kept in transparent plastic containers to full sunlight for at least 6 h [11, 13] which is slow, and is

not always feasible as a result of daily and seasonal variations in weather conditions. Solar disinfection can be enhanced substantially by using certain photocatalysts such as the photoactive semiconductors TiO2, ZnO, Fe2O3, WO3 and CdSe. These photocatalysts produce highly reactive oxygen species (ROS) which destroy microbial pathogens; this is known as solar photocatalytic disinfection [14, 15]. Titanium dioxide (TiO2) is one of the most widely used, stable and active photocatalysts in water disinfection [8]. It has shown its effectiveness not only ifenprodil in small-scale solar disinfection reactors but also in pilot studies of large-scale solar photocatalysis for drinking water and waste water [16–19]. Typically, TiO2 slurries are used for chemical and microbial photodegradation [9, 19]. However, such slurries create problems in separating the photocatalyst from the treated water, leading to the development of reactors containing an immobilised photocatalyst. Different types of solar photocatalytic reactors have been developed for water treatment [20]. The most frequently used types of reactors are: (i) the parabolic trough reactor (PTR), (ii) the double skin sheet reactor (DSSR), (iii) the compound parabolic collecting reactor (CPCR) and (iv) the thin-film fixed-bed reactor (TFFBR).