Cooling tower fill comes in multiple different styles that have different efficiency levels, pros and cons. The cross-corrugated fill that is used in many cooling towers can be extremely efficient because it offers the most surface area possible, exposing the most water to the most air possible, but because of this design, it’s easy for contamination to take place. This is often called “fouling†and cross-corrugated fill is known for being susceptible to fouling. Fouled film fill will always reduce cooling tower performance