Sorry for this long post, but I think it is relevant.
Please reread what I wrote. In canisters where I use traditional media I have to clean them twice a year, Where I use 100% Poret foam I have not opened the filter in 3+ years. I run Hamburg Matten Filters on three tanks and barely have had to clean the foam. I rinse traditional sponge filters every week, I rinse my Poret cubes about once a month. My cleanest looking water is in tanks where there is no dedicated mechanical filtration at all, just massive ppi controlled foam.
If you put mechanical filtration in front of bio, your filter clogs way way faster. Please read this article
Aquarium Biofiltration It took me a lot of years to learn that filter floss is not my friend, it clogs way to fast and that impedes the functioning of bio-filtration. It can also damage pumps that power filters as the intake side should never be blocked. Or take a look at how Eheim suggests one load their canisters. The filter floss is thr final stage not the first. In the earlier flow they do use a coarse foam. But that just allows the larer organisims to break the waste into smaller pieces which wont clog things as they move through the filter system and keep getting consumed.
In my smaller filters such a AquaClear hang-ons, I use two sponges with floss between them. That is a compromise. In some there is no floss. I use the floss because the is not sufficient media to host all the needed organisms before the water exits. So I have to catch some gunk with the floss
What does that mean for aquarium biofiltration?
Water filtration is teamwork by the members of the substrate microbial community from all domains of life. This is an important conclusion, both for freshwater and marine habitats. The different players form a food web, where most organisms cannot exist alone but are interdependent. The microbial community varies greatly depending on the availability of foods, pore sizes, and substrates. Soil biofiltration is therefore very plastic, meaning it can cope with a variety of conditions. However, one feature is common. Natural layers of biofiltration are usually undisturbed for longer periods of time (many weeks and months). In nature, no one squeezes out the debris or rinses the media on a weekly schedule. Occasionally, seasonal floods or rains may “wash” a gravel bed but regular rinsing of the filter media is not happening. The microorganisms eat the debris and the sludge is completely broken down into gases and soluble products that then escape the pore space. Soil biofilters are almost maintenance-free. The released substances are either getting into the atmosphere or are taken up by plants.
For aquarium biofiltration to be most effective, filters should be running undisturbed for as long as possible. Filter media that remain passable and have a variety of pore sizes are best. Given that we like to influence the water parameters depending on the species we keep, and thus make water soft, hard, etc, the filter media should be chemically inert, so that it does not affect the water chemistry by itself.
Author © Stephan M. Tanner, PhD
from the Biofiltration link above.
A filter is a pump, the media inside it is a home for the assortment of living creatures which are the actual filters. The only filter better than massive foam, imo, is a planted substrate. My favorite forum for fish is one where a number of the members are actually practicing Ph.D. level biochemists. icthyolohists etc. It has sections for both published papers and graduate school theses on fish related topics.
The vast majority of trade in fish is the aquaculture industry. It absolutely dwarfs the ornamental fish trade. Where do we think the best ideas for filtration are found?
Fish tanks?
Public Aqariums?
Aquaculture? (Hint its this.)
Next, what is the biggest difference between these three areas? Here is another clue. How easy is it to change half of the water in a
A 500 gallon fish tank
A few 100,000 gal. public aquarium
An aquaculture pond of 1 acre or more
If you want to learn about filtration, the place to look first is Aquaculture
I learned to handle nitrite using chloride from this arena. I never heard word one about it from any hobby related site. Have a read of this paper from 1997
Nitrite in Fish Ponds The scieentific community long ago decided it was uselss to research nitrate if the investigation ignored chloride levels. The results were considered worthless if they were not included.
How about nitrate? In my tanks with massive foam, I have no nitrate. I have denitrifiers in that foam. How that works is water entering the foam will move though it. In some areas the microbial community will extract all of the oxyen from the water passing though. The result is what moves deeper through the foam now contains nitrate instead of oxygen. Here a different type of bacteria lives caledl facultative anaerobes. These can use oxygen when it is present, but when it is not, they switch to using nitrate which they reduce to nitrogen gas that exits the system. This is how it works in a planted substrate. Aerobic areas are surrounded by anaerobic ones which process the nitrate creatde in the aerobic zone which used up the oxygen.
Two final facts- Archaea do some amount of the ammonia oxidation in our tanks- this varies with individual aquariums from almost 0 to the majority. Some strains of nirtospira which were identified as the major nitrite oxidizers in tanks are able directly to oxidize ammonia to nitrate. A single bacteria does both ammonia and nitrite.
In the end folks will do what they want and believe what they want. If you want the science,
Google Scholar is your friend.