Pretty much the only hang-ons I ended up using were AquaClears. I did have ab Emperor 400 on my first tanks but it quit after 7 or 8 years, I ended up with 2 ACs on the tank until it leaked and got replaced. At my peak I was running 28 ACs and all the models from the 20 -110. Initially they came with the sponges and carbon but later on they came with "bio-media." Initially I used two AC sponges with a layer of floss between them.
Over time I replaced the AC foam with Poret. But when the bags of bio-media stared to be included and the price was raised I just threw out the bio-media and bought replacement AC sponges to use in place of the included media. Eventually that became Poret foam. Then I began using a few canisters- all Eheim Pro II 2026. These came with a bag of noodles and a bag of bio-media. I used it in my first canister and it is still there 20+ years later, However on my next one I never used the Eheim media and replaced it with AC sponges. By my third one I used 100% 20 ppi Poret foam. I clean the first two canisters twice a year in June and December. The third one I clean about every 4 or 5 years when I see the return flow slowing as I was instructed by Stephan Tanner. I am about ready to do the second ever clean on it soon at about 10 years of use maybe a tad more.
It took me forever but at my club's public auction two days ago I finally sold all my never used Eheim media. I do rinse the Poret blocks in my ACs close to every week but I do not get much coming out and I never squeeze the media only swish it in a bucket of water. It is rarely dirty and this is just a habit from when it was all AC foam media.
Now I am going to burst another Urban Aquarium Myth that sponge/foam media is only for mechanical filtration, BS! I have not found any better bio-media than Poret foam. But what I really love about it is it is also a great mechanical media. What very few folks understand is that the majority of mechanical waste is actually organic in nature. This means it breaks down over time. Large foam works very much like how nature filters mechanical waste. It took Dr, Tanner and his onsite articles for me to learn the actual biological facts about this.
On the Swiss tropical site is an excellent article on this
Aquarium Biofiltration it first explains how this works in nature and then how this applies to what we use in our tanks.
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.......................
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
Since Poret is available in a variety of pore sizes, we can use all sorts of arrays. But the higher the porosity number, the finer the foam. So the faster it will clog. So, I normally try to use the 10 ppi foam for prefilters and then the 20 ppi for the rest. I determined this gave me the best compromise between the bio and mechanical fiunctions and it did a good job without clogging to soon. I do have a bit of the 30 ppi which I use for shrimp and fish fry tanks. While it would clog faster in my tanks with bigger/more fish, in the smaller critter tanks this is not an issue.
I had plans to sump system on the 125 gal. things changed and did something else, Had I done the sump it was supposed to use 3 sheets of Poret foam. First was 10 ppi, next a 20 ppi (or possibly a 2nd 20 ppi) and then a final 30 ppi. One benefit of the sheets with an inch or more open space between them is that I would be able to pull any one sheet, rinse it and return without needing to stop the filtration.
I had purchased a used 150 and 125 and a 40L to be a sump for the 125. As it turned out life changed my plans when my inwall 75 began leaking. I had to move the fish destined for the 125 with the sump into the 150. That tank runs with an Eheim, a H.O.T. magnum and an AC 110. When I finally got the 125 going is was used for plecos and had all Poret Cubefilters. I ultimately changed out one of the 5x5x5 cubefilters and replaced it with a 5x5x10 inch tower filter (just sold as lighty used at the weekend auction).
We all know that the best filtration is a well planted tank. But not all tanks can or will be done in this way. What I know from experience is that the next best option after live plants is a Hamburg Mattenfilter. These are massive foam sheets. I have a few of these and they almost never need to be cleaned. The other thing is, that over time, they will be doing denitrification to some degree and possibly completely. They host facultative bacteria which, when oxygen is present, they work one way using it, But, if the water passing through the nitrifying bacteria uses up all the oxygen, then it sends on nitrate instead.
The facultative bacteria will switch to using the nitrate and the result is they make nitrogen gas which returns to the air. Next, there are so many potential pathways through the foam that is takes a long time to clog up to where it needs to be cleaned. In tanks where I use the Poret cubefilters I usually rinse them out monthly.
And what really woke me up to how well Poret could handle mnechanical filtration was when I posted a picture of my first pleco breeding tank with a Matten filter and the first comment I got had a question as to how I got my water so clear. It was then I realized I could put a quarter against the outside of back glass of that tank and then could read the date on it standing in front of the tank.
What works for UGF filtration where the entire substrate is the bio-media also worked in the same way for a Matten made with the sort of rigid foam out of which Poret is made.
@
Magnum Man
It is simple. The finer the pore size or the holes in a bag, the better it is for mechanical filtration. At the same time it also means the faster it will become clogged. But with a bag there is only one size. This gives one both advantages. But often filters are too small for several grades of media. My choice has been to use mostly 20 ppi which works very well for me. I even use it for pre-filters at times.
Bear in mind that it is ammonia which controls how much bacteria/archaea one has in any tank. If there is big bio-media involved in the filtration then the amount of bacteria living outside of the filter media will not be great. But, if we have too little media then the bacteria will colonize elsewhere in the tank. They will abound in the top of one's substrate but there is usually not enough dissolved oxygen available by an inch deep to support them. In fact, an inch may be pushing it.
In most of my pleco tanks I wanted as much of the nitrogen consuming media to be in my filter media and not elsewhere in the tank. I encourage this to be the case by vacuuming the substrate itself not just skimming the surface. The result is it causes a loss of the bacteria in the substrate. That meant there was more ammonia then the rest of the bacteria needed which caused them to reproduce. And this meant there should be more bacteria in the media when the reproducing was done.
What I am doing is killing off some of the bacteria in the substrate resulting it being replaced by newly reproduced cells in other parts of the tank. My goal is to reduce the numbers in the substrate and to increase them in the filter media. This is why I also like to cycle filters rather than tanks when having to cycle multiple tanks at the same time. The bacteria do not really care where they live in a tank as long as what they require is continuously delivered to them where ever they are.
(I apologize from so many typos, misspelled or omitted words. I tried to fix them all)
