A new cultivar of Dianthus plant named \u2018BRIGHT EYES\u2019 that is characterized by compact habit, grey-green foliage, and double flowers that are predominantly white in color with deep plum-red centers. The fuel cell system includes a plurality of fuel cell modules include a sealed planar fuel cell stack that has internal manifold channels for transport of fuel and air to fuel cells within the stack and transport of tail gas and spent air away from fuel cells within the stack. A disturbance in the supply of substitution liquid is inferred when the amplitude of the pressure waves exceeds a predetermined limit value.