Ive noticed my emp 280 on my 55 gallon is capable of holding two carbon cartridges.i usually only use one but now i have them both filled.whats the advantage of having a extra one in the other slot on a tank.Does it really help any?
I would fill the cartridges with some sort of biomedia instead of carbon. I know the bio-wheel provides a lot of bio-filtration, but the biomedia can be used as extra bio-filtration in case something happens to the bio-wheel.
