Stocking Numbers

[AbbeysDad]

Adding larger filters or more filters does not increase biological filtration beyond what the system needs. @AbbeysDad has written of this frequently, he may have more to add here, I have been as brief as I can to get the point across. Mike has looked into this more than I have, and I'm sure other members have too.

The number and size of the beneficial biology colony(ies) is naturally dependent on oxygen and food (ammonia, nitrite, and nitrate). Manufacturers of commercial biomedias claim their products are better by virtue of surface area. This may have some merit through the tunnel vision of product to product comparison, but makes no sense when the amount of bio-media exceeds the real estate needs of the BB colony(ies).
I also challenge the notion that many hobbyists believe that beneficial biology only lives in the bio-media in the filter. This may in part be true for the newly setup aquarium, but as the system matures, beneficial biology takes up residence throughout the aquarium, especially in the substrate where in time, would dwarf any BB in any filter.
As to stocking level, I think Byron did a good job of exposing how uncertain any 'rule' would be because of so many variables. So the one inch per gallon rule is potentially incorrect even for small fish.