Talk:Aquarium filter

Disambig

If this page in the disambig for filter? I can't see it there. 124.182.247.15 10:38, 24 June 2007 (UTC)

It wasn't. I've added it now. CrispMuncher (talk) 20:58, 6 July 2008 (UTC)

Power Filter redirect

Power filter redirects here, while I guess there are powered aquarium filters I was looking for a power line filter. Not exactly sure what that is, I'm guessing close to a surge suppressor? Anyway, nothing to do with aquariums. A power filter for sale 70.20.252.106 17:11, 10 August 2007 (UTC)

Intro

The second paragraph of the introduction seems located in the wrong spot. Does anybody watchlisting this page have problems with me doing some cleanup? SaltyBoatr (talk) 19:08, 11 December 2008 (UTC)

No objection at all to that particular change - it has enhanced the article. That "In the hi-tech planted tank..." paragraph always struck me as a non sequiter anyway, and some of the particular claims were overly assertive IMHO.

I do have some reservations over the new Overview section though. The material added is technically good but it seems to me that the emphasis is misplaced. I have always regarded biological filtration as the key aspect - getting and maintaining control of the nitrogen cycle is all important. Mechanical and chemical filtration is secondary. This view is the same as that found in most books I have read on the subject, and is also shown by the existence the simple air-powered sponge filters which only really have a biological effect. However, reading this overview it is easy to reach the conclusion that biological filtration is a minor side benefit compared to the main points of mechanical and chemical filtration. That strikes me as misleading through undue emphasis. CrispMuncher (talk) 15:09, 12 December 2008 (UTC)

I see your point. It almost is a problem with the words chosen for the topic of the article. As there is an overlap between aquarium husbandry or aquarium management and the equipment "filter (aquarium)". The biological actions that converts ammonia to nitrite and that then converts nitrite to nitrate occurs naturally on all substrates in the aquarium and isn't technically filtration. "To filter" means to remove solids from a liquid, or dust from a gas. And, by extension, to remove impurities from a solution. Even then, the biological action just transforms one toxic nitrogen molecule into another less toxic nitrogen molecule and doesn't really remove anything from the water. That said, I think that readers do come to the article to learn about aquarium management, and I agree that the biological effect is paramount and deserves a major emphasis in the article. Feel free to do this yourself, and I intend to keep trying to improve the article through editing and the addition of additional emphasis on the biological 'filtration' in the near future. I am happy to collaborate on this. SaltyBoatr (talk) 16:15, 12 December 2008 (UTC)

I see you've done some work on this since I left my first message. I still think it needs a little more work. I'll try combining the various elements of the introductory portion together and see how that works. CrispMuncher (talk) 20:47, 12 December 2008 (UTC)

I've now integrated these elements together into a single overview section with sub-sections for the biological and other filters used. It seems to follow a more logical progression now, and I've filled out the details of the nitrogen cycle a little. There are one or two snippets that I considered minor points which I left out because they didn't really fit in anywhere as I was drafting the revised version (sorry, don't immediately recall what they were now). Happy to collaborate (makes a nice change to constant disputes) and feel free to make any changes you see fit. CrispMuncher (talk) 22:10, 12 December 2008 (UTC)

I kind of disagree that biological should come before mechanical. The sequence of events starts with the solids. The, if the solids are not filtered out, then they decay into solution, and biological action occurs. Also, I have concern that the nitrogen cycle is not really technically "filtration". SaltyBoatr (talk) 02:22, 13 December 2008 (UTC)

I would tend to disagree regarding the ordering. OK, the process starts with solid matter for the most part but most solid matter never reaches the filter (which is why the gravel gets so mucky). They are also not lost from the tank when captured by the mechanical filter - they continue to decompose as normal. Since we both agree that biological filtration is foremost in importance it makes sense to me to have that first. Having said that I am not too fussed either way - switch them around if you like, although that "A final and less common..." sentence will need some work if you do.

On the subject of whether biological filtration is really a form of filtration, common usage in this area suggests that it is. Even if it is not in a technical sense (which I will come to in a minute) we are best using the terminology generally used in this particular domain and not being so pedantic. There doesn't appear to be much consensus on whether filtration must be a purely mechanical process or not. The filtration pages suggest that it must be but most dictionaries I have consulted vaguely refer to removing impurities without discussing mechanisms by which this is done. I'll leave a note on that article's talk page and see if anyone has any input there. CrispMuncher (talk) 21:25, 14 December 2008 (UTC)

I guess we are debating WP:OR a bit here. It seems obvious to me that in principle with high flow rates and large filters, you could mechanically filter out all the solid waste and reduce the source of decay and vastly reduce generation of ammonia. Also, the nitrogen cycle doesn't actually remove impurities at all. Biological "filtration" does nothing other than de-toxify, leaving 100% of the nitrogen in the water. I guess, that we are discussing principles of tank maintenance now. Is the article about aquarium maintenance or aquarium filters? Gunk in the gravel, especially with under gravel filters, (and even without) occurs because the gravel is acting a a mechanical filter catching solid debris because it is porous (like all filter medias are porous), and gravel gets gunky because it is difficult (and therefore because most aquariests neglect) to clean solid debris out of the gravel. SaltyBoatr (talk) 17:34, 15 December 2008 (UTC)

saturated activated carbon is dangerous????

I think the sentence "This is particularly important in the case of activated carbon filters, which may re-release their adsorbed contents in large (and therefore harmful) doses if they are allowed to saturate." pointing to the pg 33 of the book by Andrew Eade is dubious. Adhesion of activated carbon can be 'undone' releasing the adherents, but that involves heat[1]. I just don't believe that this happens spontaneously in a tank, much less dangerously in "large harmful doses". In actual practice, I believe, the more common problem is that the AC becomes clogged and spent and needs to be replaced because it is ineffective. SaltyBoatr (talk) 20:59, 12 December 2008 (UTC)

It was me that added that point. I've seen it referenced in a number of different of different sources. I admit that it sounds unlikely you have to bear in mind that we are not dealing with a mechanical filter here and everyday notions of filters getting clogged up do not apply if the filter is acting chemically. To quote the source cited:

Activated carbon, for instance, is an excellent filter media as it will absorb a variety of chemicals from the water. However, once saturated, it may release these chemicals back into the water in large doses which may be harmful to your fish. To prevent this from happening, change the chemical media regularly.

There are other sources that make the same point. The manual for my main tank (a Juwel Rekord) covers this, although admittedly Juwel have a vested interest in selling new filters:

Please note that the chemicals which are absorbed by the activated carbon contained in the sponge, will be released to the water again if the change intervals are too long.

There doesn't seem to be a huge amount on this online. What I've found seems mainly to be forums where amateurs are dismissing the point. I don't attach too much significance to those comments since I have already said it does sound wrong even if it is right, and in any case such comments are not to be considered reliable sources. The only 'professional' site I found in my brief search was http://westerncichlids.com.au/the-use-of-activated-carbon-in-aquariums/ which states:

The power of adsorption is limited and it losses its fixation capacity after several days, once it has become saturated. Even worse, it can then release the molecules it had previously extracted back into the water. Therefore, it must be replaced frequently; frequency being dependent on the saturation or concentration level of undesirable elements in the aquarium.

CrispMuncher (talk) 22:45, 12 December 2008 (UTC)

Did you see my book[2] source? I am wondering if the casual books are correct? Have you seen this article[3] by James R. Layton? It sure looks like getting activated carbon to give up what it grabs is not an easy thing to do, and it seems incredible that it can happen spontaneously. What could trigger the spontaneous release of chemicals back into the tank in large amounts? I am guessing that these books you are reading are parroting an urban myth. SaltyBoatr (talk) 00:48, 13 December 2008 (UTC)

It took a little reading up (and dusting off my A level chemistry) but I think I've got it. The key to understanding this is that the adsorption/desorption process is a reversible reaction. This does not mean that the reaction can be persuaded to go one way or the the other: it means that in any given system both processes are happening simultaneously. If for a moment, consider the stable situation, with a saturated filter and some nasties in the tank. Some pollutants are being released by the filter but this is conterbalanced by the pollutants that are still being taken up by the filter. This is "dynamic equilibrium" in the language of reversible reactions - the net effect of the two processes is nil but they are still taking place.

If we do a water change we disturb the equilibrium - there are less pollutants in the tank and so the amount taken up by the filter decreases. However it continues to release pollutants at the same rate so the net effect is that the filter releases nasties until a new equilibrium is reached. This isn't in itself harmful as the new balance will still be at a lower level of water-borne pollution than before the water change. I found various posts along these lines in the Google groups archives - I'm sure you can dig them up yourself if you want. I also found a scientific paper dealing with this issue in a different context at http://pubs.acs.org/doi/pdf/10.1021/ie060909b This paper shows the point with air filtration - once you supply clean air the filter itself acts as a source of pollutants because the equilibrium has been disturbed. The sources you cited on regenerating filters are using the same effect for a practical purpose - the conditions shift the equilibrium point far to one side of the equation, and the net effect is to almost completely purge the filter of previously adsorbed material.

However, the sources cited deal with specific cases where a single substance is filtered out: they do not deal with our circumstances. We are not filtering out a single compound but a broad range (hundreds, perhaps thousands) of different molecules. Each of these will have different dipoles (basically, the electrical charge is not evenly distributed within the molecule). The molecules with stronger dipoles are more likely to be caught by the filter, and once on the filter are less likely to be released. If the filter is new this isn't a problem since there is plenty of capacity to absorb all the molecules in question.

However, with a saturated filter there are very few sites on the filter left where new molecules can attach. Suppose with have two different molecules A and B, and B has the stronger dipole. The bulk of the molecules released will be A instead of B, since it is less tightly bound to the filter. However, the site it was released from is now available, and it is more likely that B will bind to this site because of its greater dipole. There now isn't a site for the molecule of A to reattach to. The net result is a tendency for a saturated filter to begin dumping A in favour of accepting more B. This could well mean that the levels of A pass acceptable levels it in the tank. Bear in mind that in the real world we are dealing with many molecules and many different molecules will be released from a saturated filter. It only takes one of them to pass acceptable levels for trouble to arise.

Of course, this is based on supposition and is inherently OR. However, we already had reliable sources quoted documenting the issue and you wanted a mechanism. That proposed above seems not just reasonable, but inevitable to me, but we could probably use some expert attention on the subject. CrispMuncher (talk) 22:17, 15 December 2008 (UTC)

That pdf paper was helpful, thanks. From the page 5 conclusion, two de-adsorption scenarios were observed, both depending on equilibrium shifts. 1) It would be reasonable to conclude if you shifted activated carbon from a contaminated tank to a pristine tank, some contaminates would de-adsorb into the pristine tank. Or 2) if the filter pump was deactivated de-adsorption would occur into the filter chamber, and then if the pump was reactivated contaminates would be pumped into the tank.

Neither of these scenarios are reasonable possible in normal circumstances. (Greater than 20% water changes are ill advised. Shutting off the fiter pump is ill advised too.) Therefore, I still think the Andrew Eade citation is dubious. SaltyBoatr (talk) 22:46, 15 December 2008 (UTC)

Sorry, I went on a wikibreak and forgot completely about this discussion when I got back. The amount of water changed is an irrelevance to shifting the equilibrium point - it is a continuously variably thing ratehrthan being triggered by a certain threshold. If you add so much as a teaspoon of clean water to a tank you slightly dilute the pollutants in the tank. In response to this the filter will leech some of its contents. A tiny amount because of the small amount of dilution, but it does happen.

However, in response to selective behaviour in a neraly saturated filter - this does happen. It is a regular displacement reaction. I found a link: http://books.google.co.uk/books?id=zGNwoTe0Yq4C&pg=PA6&dq=adsorptive+displacement+activated+carbon&ei=HagySpzyFpqwyATX0JWUBg#PPA9,M1 which appears to go through this, although I have not re-read this today - I bookmarked it months ago. In any case, searching for explantions for this in pure chemistry texts is not appropriate here. This is an applied subject and applying pure chemistry is inherently OR without a source making the connection. The sources within this applied domain seem to indicate the dangers of saturated carbon filters. CrispMuncher (talk) 19:19, 12 June 2009 (UTC)

nitrogen cycle diagram

For consideration.

I'm not sure about that picture, but a section on the nitrogen cycle would be entirely appropriate. — Preceding unsigned comment added by 173.25.128.114 (talk) 13:06, 18 October 2011 (UTC)

Removal of biorb material

I've removed the whole biorb section since it doesn't look like it belongs here at all. I see from the edit history I am not the only one with this view. For coverage of a particular proprietary implementation that system has to be unique in some manner. For all the marketing stuff, there is not really anythnig different about the Biorb system. Pretty much every aquarium manufacturer has their own multi-stage filter system with their own proprietrary filters. There is nothing distinctive about the Biorb system. CrispMuncher (talk) 19:01, 12 June 2009 (UTC)

Tone and style

The tone of this article is very lecture-y. It's loaded with words as phrases such as "critical" and "necessary" and "important", which may be fine for a "how to" article, but are out of place in an encyclopedia. It should be "this is what it is, what it does, how it does it" not "this is what you should do and why". I'm not familiar enough with the subject to be comfortable trying to differentiate between statements of fact and statements of "correct practice" (which is why this tone is a problem), so I'm asking the people who edit it to try being less know-it-all preachy and more neutral/factual. -Jason A. Quest (talk) 16:06, 30 September 2013 (UTC)

You make a good point. A lot of it is something that's rather endemic with aquarium-related pages, which is WP:NOTHOWTO. --Tryptofish (talk) 17:22, 30 September 2013 (UTC)

Hamburger Mattenfilter not yet in english wikipedia

Since I started to have an aquarium for a second time about 10 years ago I learned about a simple kind of internal filter, the de:Hamburger Mattenfilter. It is since then the only kind of filter I am using in my currently two aquariums. It appears to be mostly known in (and around?) Germany. There are some web pages that explain the theory behind it. And already two internet shops that sell this kind of filter. For an english page, see for instance Introduction to Hamburger Matten Filter HMF.

In the German article for filters in aquariums it is listed as one of three type of internal filter: de:Aquariumfilter.

I would like to add a statement about this. Does anyone know whether there exists a proper english translation for this? Or should I use "Hamburger Mattenfilter"? --Malanoqa (talk) 20:05, 19 January 2017 (UTC)

Thanks for asking. I'd be reluctant to add anything that would come across (per policies at the English WP) as promotional. It would be best to be able to cite reliable sources that establish that this is something that is widely used. I'm not aware of it being used very much outside Germany. --Tryptofish (talk) 02:15, 20 January 2017 (UTC)

Hi Tryptofish, my intention is not to promote a shop or a product. But to share knowledge that is available for a certain language with the Wikipedia of another one. I searched the policy list, but found (yet) no policy that I can use to check whether this is to be rejected as promotional.

Generally I do understand that each language Wikipedia has own roles to define what is relevant. But to my understanding the Wikipedia articles should not be specific to a certain country unless they are specifically aimed to be so. I guess that the relevance criteria for German and English Wikipedia are related. So either a statement about the Hamburger Mattenfilter is appropriate for both Wikipedia versions or for none of them. That a certain technique is used mainly in countries that speak only one or a part of the languages should not be a criteria. So if there is no reliable sources for the Hamburger Mattenfilter, the statements should not be in the German and in the English version. As the language of the source does not matter as far as I know (But sources of the same language are preferred).--Malanoqa (talk) 13:55, 22 January 2017 (UTC)

Thanks for that very thoughtful answer, and I definitely have no concerns at all about your intentions. Please let me make the following suggestions: (1) Per WP:DUE, limit the amount of text on this particular filter to be no more than what other types of filters are given on this page. (2) Please cite a secondary, rather than primary source, if at all possible. It's fine if the source is in German instead of English. (I don't read German, but that's no problem.) (3) If it happens to be true that this filter is mostly used in Germany but not elsewhere, then say that explicitly. I'll be happy to copyedit the material after you add it. Thanks! --Tryptofish (talk) 19:50, 22 January 2017 (UTC)

No picture for some filters

There should be at least one picture for each kind of filter. That's not the case.

And the article should link, at the very end, the method for having a tank without electricity-operated filter, Walstad or other methods. — Preceding unsigned comment added by 87.91.248.85 (talk) 13:27, 27 October 2018 (UTC)