phillydog1958;3746339; said:Biomax is made of ceramic, while bio balls are made of a plastic material. Why can't bio balls be used in an FX5? I don't understand how the efficacy of bioballs can be questioned when compared to Biomax. I would think that both products would allow for a satisfactory result. Are you implying that biological bateria is more attracted to ceramic, versus plastic?
Bio balls would be fine and in fact depending on the bioload a better choice since they are less prone to biofilm clogging than finer pore ceramics.