Which Eheim Filter Do I Need?

[TwoTankAmin]

You will get a much more robust biofilter than most folks in the hobby have. It will do a lot more than nitrification, it will break down organics, it will even do some denitrification.
 
But it is not the filter that does filtration, it is not the media that does the filtration. All they do is create a proper home and supply nutrients to the micro-organisms that do the filtration.
 

 
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

 
The Poret is providing the above. You wil have huge surface areas to trap particles and break then down, to make ammonia along with what fish exhale to feed the nitrifiers. Organics get trapped and broken into ever smaller sizes until they get consumed by other tiny things in the foam.
 
Think about how much surface area is made available for biofiltration with the Poret vs noodles, ceramics, normal sponges. And because there is such great volume of media compared to the normal loading for hang on filters or even other media in caisters, it takes a very long time to clog up and need a cleaning.
 
But inside all that foam are most of the same things one would have living in a planted tank substrate or would find in nature keeping the water clean. The more media one can have, the better the filtration potential.
 
The thing about this hobby is there are many ways one can accomplish the same goal. A lot of what is repeated about filtration doesn't come from science but from manufacturers. They are interested in selling products. Therefore they will almost always favor methods that required repeated spending on something. So consider your Poret foam filled canister which should only need to be cleaned once every year or two and the media in it should last at least 10 years.
 
Don't worry about the empty space on the bottom of the filter. just use the baskets. And the bottom one should be the first in line for flow. Ween you cycle the tank you do it no differently than for any filter or tank.

 

[RinaLane]

TwoTankAmin
thank you! getting poret then

 

[TwoTankAmin]

If you want an idea of how larger well made filter media compares to what most of us have been used to, consider this.
 
I have a 20 gal. long tank for growing out pleco youngsters. I am almost finished swapping out the 3 hang-ons that used to be on the tank. I had an AquaClear 150gph and a 100gph plus a Tetra Whisper 100 gph.
 
The Aquaclears each had two sponges and a layer of floss and the Whisper had a bit of floss and pieces of sponge in it.
 
2 sponges in the 150 @ 3.5 x 2.25 x 1.62 = 12.76 cu. in. x 2 = 25.52 cu. in.
2 sponges in the 100 @ 2.375 x 2.25 x 1.625 = 8.67 cu. in. x 2 = 17.36 cu. in
Pieces of sponge in the Whisper  estimated to be = 10.00 cu. in
 
So the total volume of the sponge media in all three filters was about 53 cu. in.
 
These are all being replaced by a Matten filter that is 11.75 x 11.5 x 2.0 = 270.25 cu. in.
 
As you can see the Matten, w/o considering the PPI involved, is over 5 times the volume of the hang-ons combined. But if we were to calculate the available surface area for the bacteria etc., the amount of surface area in the Matten is going to be more like 10-20 times that of the other three filters combined. Even better, I am running that filter from a single air pump which draws less power than the three hang-ons did.
 
And then there was the fact that I was rinsing the media and changing the floss weekly in the hang-ons and and I doubt I will have to clean the Poret but once every year or two, my weekly work load on that tank is being reduced by about 50. I will still vac some and change the water, but I wont need to deal with the filter at all.
 
I just installed a Matten filter on a 33 long. This one replaces and AquaClear 300 and a pair of powerheads which have moderate size intake sponges. That Matten is 3 inches thick and offers over 414 cu. in. of media volume. Since this is a breeding tank for plecos it will get a supplemental pump hooked to a spraybar to produce more current driven from the far end from the filter. The Matten itself is powered by a variable speed pump with the flow rate adjusted down to about 160 gph. I also rigged a custon sopraybar return for it as opposed to a single Jet Lifter.

 

[RinaLane]

Ordered 2" black 20ppl foam so far. Sadly eheim I ordered came broken & I have to wait longer to get replacement Very upsetting.