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Foam placement in an external filter

swackett

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29 May 2008
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Surrey
I recently watched several videos by Pondguru, he says its best to place mechanical filtration in lowest basket as that is the first basket the water passes through after the pre-filter foam. As the mechanical filtration is teh first backet the water encounters, it leaves the biological filtration free from detritus and muck. He also advices to use fine, coarse and medium foam as mechanical filtration rather than ceramic tubes.

What are your views on this, is this good advice, should I try it ?

Thanks
 
In my opinion he’s right to order mechanical filtration from coarse to fine, followed by biological medium. However, he never mentions that foams actually perform biological filtration. I don’t agree with his use of fine floss as the last stage though as it clogs up too quickly.
 
In my opinion he’s right to order mechanical filtration from coarse to fine, followed by biological medium. However, he never mentions that foams actually perform biological filtration. I don’t agree with his use of fine floss as the last stage though as it clogs up too quickly.
Well.

According what he is saying he is against of using filter floss at all.

I’m going to try that and see what happens.
 
try without the fine "polishing" filter floss pad?

I'm using ceramic tubes at the moment and he seems to say they are not very good at mechanical filtration.
 
All depends on what filter you have as some will start the filtration process from bottom to top and others top to bottom.
What filter is it??
 
Hi,
120419050424.jpeg
32390736836_914417c2ed_o.png

As you can see the water is pre filtered at the top then flows to the bottom and back up through the media baskets.
It's entirely up to you with what and how you fill these baskets but I would always use the prefilter sponge in the top basket.
For reference I've got the 2180 which is identical in operation to the 2074 and I load it as Eheim suggest but only using a very thin almost see through layer of Substrat Pro in the bottom 3 baskets. I change the polishing pad every 3 to 4 weeks when I clean the filter (which is always pretty clean anyway). I know some people worry about denitrification in this pad but I personally have not encountered any problems in the last 5 or more years of use.
I personally don't hold Pondguru in very high esteem with regards to planted tanks, I think his methods are more suited to fish only tanks with the caveat of cramming them full of his own brand media.
Cheers!
 
Hi all,
I recently watched several videos by Pondguru,
I just wouldn't regard him as a <"reputable source">. There might be things he is good at, but in the areas that I have expertise in he has made some very, very questionable statements.

In terms of mechanical filtration, I don't personally like <"any inside the filter body">.
....... I think that is a major issue straight away, <"the name "filter" implies"> that mechanical filtration is the important bit and that the filter is an <"aquatic vacuum cleaner">, sweeping up visible debris and then retaining inside the <"vacuum cleaner"> body. I think this also leads to the the conclusion that the <"vacuum cleaner bag"> only needs emptying <"when the bag is full">, but nothing could be further from the truth.......

cheers Darrel
 
Hi all,

I just wouldn't regard him as a <"reputable source">. There might be things he is good at, but in the areas that I have expertise in he has made some very, very questionable statements.

In terms of mechanical filtration, I don't personally like <"any inside the filter body">.


cheers Darrel
We currently have the pre-filter foam in the prefilter tray at the top, then from bottom basket upwards, Eheim Mech ceramic tubes (took the Eheim mech pro out as they kept floating up when cleaning the filter and removing baskets), next basket is filled with Eheim Biomech, next basket is Eheim Substrate pro, then the top basket is Eheim Substrate pro with a "polishing" pad on top.

Is this optimal, recently I moved the "polishing pad" to the top of the bottom basket. I guess does it matter that the biological filter media gets clogged up with detritus ?

I was thinking of adding more biological substrate Pro by replacing the Eheim Biomech.

Also does the media need replacing after many years of use? if the media gets clogged up with detritus then does that mean the small holes and surface area is then lessened?
 
I guess does it matter that the biological filter media gets clogged up with detritus ?
Yes, it matters. The idea of mechanical before biological is to keep the biological free from debrismthat would otherwise clog it and slow down flow through the media. Hence the use of pre filters (which should be cleaned often).
 
Hi all,
Is this optimal, recently I moved the "polishing pad" to the top of the bottom basket. I guess does it matter that the biological filter media gets clogged up with detritus ?
The idea of mechanical before biological is to keep the biological free from debrismthat would otherwise clog it and slow down flow through the media. Hence the use of pre filters (which should be cleaned often).
That really. I use a <"big sponge blocks as a pre-filter">.

I just want the biological filter material to be <"continually exposed to oxygen rich water">, so that the <"Biochemical Oxygen Demand"> never exceeds the <"dissolved oxygen (O2) supply">.

My opinion is that <"everything else is really just froth">.

cheers Darrel
 
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You make it more complicated than it actually is; misguided by manufacturers of aquarium filters and filtration media. Actually, you don't need any biological filtration because microbes in the tank (mostly in the substrate) will take care of it, anyway. What makes some sense is mechanical filtration - to catch particles of various size - and optionally chemical filtration - to remove or replace various dissolved species.
I guess does it matter that the biological filter media gets clogged up with detritus ?
There are basically two types of biological filtration:
(1) Decomposition of organic matter - both particulate and dissolved - into mineral species. Microbes will do it no matter what you do, wherever there is organic matter, water, and preferably oxygen. These microbes with their biofilms will colonize and clog any surface, no matter if porous or not.
(2) Nitrification of ammonium into nitrates. Nitrification microbes are not interested in organic matter, and they are outcompeted wherever it is due to presence of decomposing microbes. So, they prefer niches poor in organic matter. Again, no worry, any tank with any substrate can host them with or without any filter.

Summary: Your biological media will get clogged no matter what, but it will do no harm no matter what. You can keep them or throw away, as you please. For mechanical filtration, a sound strategy is to arrange them from coarse to fine (in the direction of the water flow). The only advantage of such arrangement is that your filter won't get clogged that quickly. And that's all (unless you're interested in chemical filtration).
The main benefit of these filters is that they make water flowing. You can get the same effect with a simple water pump, which is far cheaper (and safer - no risk of water leakage).
 
I recently watched several videos by Pondguru, he says its best to place mechanical filtration in lowest basket as that is the first basket the water passes through after the pre-filter foam. As the mechanical filtration is teh first backet the water encounters, it leaves the biological filtration free from detritus and muck. He also advices to use fine, coarse and medium foam as mechanical filtration rather than ceramic tubes.

What are your views on this, is this good advice, should I try it ?

Thanks
Here is my point of view about sponges in filters in planted tanks. There are more problematic than anything in my opinion (unless you like opening your filter often), despite the fact that they can host large amounts of bacteria. This is because they can clog fairly fast, thus reducing water flow quite considerably. The only place I use a sponge is in the pre-filter to catch large debris. In my case, the pre-filter can easily be cleaned (without even stoping the filter) contrary to opening the filter and cleaning sponges that might be in it.

Unless you are running a bare tank a large majority of bacteria will be in the substrate/plant. That is why my canister only have biological media, and the only reason why I don't just run the filter empty of any media is because when you reset a tank, either partially or fully, you are happy to have a cycled filter ready to rock.
 
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