Let me give you an analogy for ceramic rings or any fine pore media. It is the "Lake" analogy used in Fractals in higher Calculus classes for anyone that has gotten that far. Pretty much when you look at a lake on a map, you can measure out the perimeter and say with certainty that it is however large. But if you get a larger map with more detail of the shore line, you will measure out a much higher number because the shore line isn't really a smooth shape and it actually waves back and forth. If you were to drive to the lake and measure it by walking around it with a pedometer, you will get an even larger measurement because you were able to measure more detail. If you measure around the individual rocks on the waters edge the measurement will approach infinity. This is compounded if you were to also measure around the grains of sand. The question presented in Fractals is "How can an object with a fixed volume or area have a perimeter that is infinite in size?" 
Anyway, the same thing applies to fine pore media. No one has actually measured them at detail. They just found an average pore size and made an estimate of the surface area. If you were to measure a piece of a fine pore media, you would say that it were, say one square inch but the marketing pro insists that it is something bizzar like ten square inches. Then when they hire a math wizard that uses the fractal principal, he comes up with 20 square inches. In the end, you put it in your sump and six months later it gets a layer of growth across it and it is back to your original one square inch.
Ever wonder why Matrix recommends replacement every six months?
Anyway, the same thing applies to fine pore media. No one has actually measured them at detail. They just found an average pore size and made an estimate of the surface area. If you were to measure a piece of a fine pore media, you would say that it were, say one square inch but the marketing pro insists that it is something bizzar like ten square inches. Then when they hire a math wizard that uses the fractal principal, he comes up with 20 square inches. In the end, you put it in your sump and six months later it gets a layer of growth across it and it is back to your original one square inch.
Ever wonder why Matrix recommends replacement every six months?
