This is a sponge filter marketed by Swiss Tropicals called the Hamburg Matten filter (HMF). The simplest version is called the “Mattenfilter” by Swiss Tropicals and is simply an an air lift tube with a piece of thick urethane foam designed to go across the entire width of the aquarium. This “across the tank” option is very unattractive and I do NOT recommend it simply because of aesthetics.
I can recommend the Swiss Tropical “Cornerfilter”. These use two siliconed in place brackets to hold a piece of urethane foam in a radius in the corner of the aquarium. Swiss Tropicals supplies an air lift tube with each kit. I recommend throwing out the air lift tube and placing a pump behind the foam to pump the water over the foam and back to the aquarium, as is shown above.
These “Cornerfilters” have the following obvious problems:
- They are only slightly less ugly and obtrusive than a sponge filter.
- It is virtually impossible to clean the mechanical filter bad gunk without also cleaning out the beneficial biofilter good gunk.
- It is really difficult to get the foam out of the aquarium without really messing up the aquarium.
- It takes up a lot of space in the aquarium
.
But note that this filter CAN be done in such a way as to give very good filtration and crystal clear water. It is a good cheap option for smaller aquariums. One has to add a pump which pumps the water OUT of the Matten filter into the aquarium. Point the outlet of the pump up at the surface of the water at about 30 degrees to optimize the amount of “choppy waves”. Size the pump to put at least 2X turnover through the foam.
Then simply don’t clean the filter until the foam starts pushing in (i.e. do not do any mechanical filtration). Only use the 20 ppi foam, not the 30 ppi foam. This can give very clear water as the foam used with this is a very good media. Note that air lifts won’t give enough flow to do a good job.
.
Swiss Tropicals has made some improvements in regard to aesthetics. Black foam is available now, which is much less of an eyesore than the blue, and the white plastic rails that hold the Poret foam in the image above have been replaced with clear rails.
A tip for maintenance: one can cut the foam above the substrate line before installation. The above-ground portion can be taken out and serviced if necessary, and the lower portion stays behind to prevent the substrate from shifting.
And one can buy foam over the internet quite cheaply and get clear plastic “L” sections (used to protect the corners of plaster walls) from your hardware store. Cut the “L” sections to size, glue in place, and one has a DIY version of the “Cornerfilter” which is much cheaper than the Swiss Tropicals version. There are several YouTube videos on how to do this.
Hydrodynamic Filtration
There is an American made variation on this filter, the Aquatica “hydrodynamic filtration” filter. It is basically just a precision cut piece of foam which goes completely across the width of the aquarium. There are one or two air lift tubes which provide the flow. This filter doesn’t use brackets but obviously at the front to your aquarium there will be part of the aquarium visible as blocked off with foam. This is just not an attractive option for a decorative aquarium. It might be useful for a breeding or quarantine aquarium.
Bottom of the Tank Matten Filter
Another interesting type of Matten filter is placing a piece of charcoal colored foam across the bottom of the aquarium over under gravel filter plates. We discuss this in this article:
8.7.7. Bottom of Tank Matten Filter
.
Return to Filter Menu
Return to Miscellaneous Filter Menu
.
Aquarium Science Website
The chapters listed below or on the right side in maroon lead to close to 400 articles on all aspects of keeping a freshwater aquarium. These articles have NO links to profit-making sites and are thus unbiased in their recommendations, unlike all the for-profit sites you will find with Google. Bookmark and browse!
.
Anonymous says
If for some reason she doesn’t like the look UG filters. Do you think the internal static sump with foam or scrubbers would also work?
David says
Good to know. I will give her your suggestion. If for some reason she doesn’t like the look UG filters. Do you think the internal static sump with foam or scrubbers would also work?
Dave says
You are correct. These are both myths that have been around for years. No animal “passes” or “swallows” things too large for it to “pass”. If goldfish were such an animal they would have ceased to exist millenniums ago. I had many UGF goldfish tanks for many years with no problems.
David says
We watched some videos with people saying that they can swallow it and it can get stuck. They also say that because they are scavengers, they prefer more of course sand to pick through. Are these not true then?
Dave says
In reply to Dave …….. It is a myth that fancy goldfish don’t do well with gravel
Dave says
See wants to keep fancy goldfish, which don’t do well with gravel. What about a static internal sump stuffed with foam or pot scrubbers?
Dave says
In reply to Dave ….. Wouldn’t work as the flow through the filter media is too far. Your best bet by far is a powerhead operated undergravel filter.
Dave says
My wife wants to build a coffee table aquarium, so we need to hide the filtration inside the tank. Seems like matten filters could offer a huge volume of media. But they are ugly as you say.
What would happen if we glued a mirror (or black glass) on one side of the tank to make a narrow compartment to hide the matten (leaving space at the bottom for water to flow under. Do you think it would still work or would that interfere with the flow of water through the sponge?
Also, is there any limit to how thick the sponge can be?