????? 水族箱內有機物質的積累導致水質逐漸污染，這些有機物主要來來自于飼料殘渣的腐爛和動植物的代謝物。隨著時間推移這些垃圾的積累會妨

礙水族箱內生態系統發展，危及魚類和植物的生長，過多的垃圾會致使它們中毒。“水的自凈化”是現代普遍高密度飼養的水族箱無法企及的奢望。

過濾，則試圖緩解這個問題。除了重要的生化降解外，過濾還必須有效的除去水草殘葉、懸浮微粒和細小物質以獲得清亮的水質。
????? 第一部分：過濾咋弄才好啊
????? 僅僅通過微細孔隙過濾（比如滲透過濾）這種物理的方式想要集中所有的污物是不大可能的。只有較大的懸浮物質如水草殘葉或飼料殘渣能通

過這種方式濾掉。如果要通過孔隙過濾去除水中的懸浮物質，那么過濾的孔徑不能超過0.0005mm，而在這個孔徑下，由于過濾阻力的存在孔隙幾乎立

即就會被堵塞。要去除所有的懸浮物，孔隙大小的選擇應該滿足能夠截留所有大小超過光波波長的微粒。這解釋了為什么再厚的纖維濾材也無法消除

渾濁。
????? 那么水族箱的過濾器如何才能凈化水質呢？孔徑達到幾毫米的濾材又如何能截留微小顆粒呢？物理過濾肯定無法做到！它是通過一種稱之為電

－化學的機制實現的。在濾材表面的蛋白質微粒（大小0.001－0.00001mm）會改變電化學特性，從而喪失其溶解性而附著在濾材的表面。隨著蛋白質

顆粒的積累，就在濾材表面形成了一層蛋白質膜。
????? 這層蛋白質膜具有很高的吸附能力，能吸附細小顆粒。這就解釋了為什么剛剛投入使用的或者剛剛清洗過的過濾器的過濾效果會不理想，因為

濾材上沒有足夠的蛋白質附著，所以吸附能力在一段日子內暫無法有效形成。若試圖以頻繁清洗過濾器來對付渾濁往往適得其反，因為濾材上的黏性

蛋白膜被破壞了。頻繁更換濾材同理也會引起渾濁。濾材的表面積越大，對微細顆粒的吸附能力越強。然而，過于粗糙的濾材結構是無法形成理想的

吸附層的。因此陶瓷環并不是非常理想的濾材，使用Eheim的Ehfisubstrat（濾材）則能夠獲得非常好的效果。

????? 第二部分：傳說中的生化過程
????? 接下來，細菌就開始降解工作了。細菌以部分降解的蛋白質（氨基酸）作為食物，發揮降解作用，氧化過程中所產生的低能量代謝產物又可以

滋養其他細菌。水族箱的水中有機污物的主要成分就是不同種類的蛋白質降解物，這些有機物（礦物化）化合形成無機化合物。因此水中無機物逐步

累積（例如硝酸鹽和磷酸鹽），這類物質比起他們在生化過濾前形成的氨、亞硝酸鹽來說在生理學上危害非常小，魚類能忍受高濃度的這類物質。
????? 簡單說來，上述的礦物化過程如下：蛋白質被分解成多肽，然后再分解成氨基酸，進一步分解成銨/氨（與pH值有關）和二氧化碳，銨或氨再

通過細菌的氧化，先變成亞硝酸鹽，最終變成硝酸鹽。這是一個非常難以置信的過程，不幸的是它有一個最大的缺點：細菌數量不夠時便無法有效工

作。新缸建缸時，細菌隨著器材和設備等一同被引入缸中，早期階段菌群規模不夠，于是它們便無法充分地完成上述過程。當環境條件適宜時，細菌

繁殖是非常迅速的，約每20－30分鐘分裂增殖一次。然而，即使這樣仍然需要最少3－4周的時間過濾器才能達到完全降解物質的階段。在這段等待時

期內，水族箱是不能夠飼養魚類的，為什么？如前所述，氨基酸的分解需要兩個階段，銨/氨到亞硝酸鹽再到硝酸鹽，這個過程中兩種起決定性作用

的細菌分別是亞硝化單胞菌和硝化菌。蛋白質降解初期，大量的銨/氨放出，亞硝化單胞菌逐漸開始將之轉化為亞硝酸鹽。大約需要20天亞硝化單胞

菌才能繁殖到實現及時有效的轉化氨/銨為亞硝酸鹽的階段。而在這段時間里，由于沒有足夠的亞硝酸鹽作為食物，硝化菌無法大量繁殖，只有當亞

硝基單胞菌能提供足夠的亞硝酸鹽后，硝化菌才能開始將亞硝酸鹽轉化成硝酸鹽的過程。這個過程也需要大約20天。所以，菌群的繁殖速度決定了過

濾器的磨合周期大約在3－4周。使用以前用過的舊濾材能夠縮短這個周期。然而，這只是蛋白質降解產物的一小部分，從化學的觀點來說，蛋白質含

碳、氫、氮、硫、磷元素，降解的過程中這些成分轉化成二氧化碳、水、硝酸鹽、磷酸鹽和硫酸鹽。盡管魚兒能夠忍受水中高濃度的硝酸鹽、磷酸鹽

和硫酸鹽，為了避免這些水族箱中這些最終產物的不斷積累而過量，定期換水仍然是絕對必要的。

????? 第三部分：過濾器里的垃圾是啥？
????? 在所有的水族箱過濾器里都能找到褐色的淤泥，而這種淤泥狀污物又是什么呢？是食物殘渣？糞便殘留物？蛋白質沉淀？或者是他們的混合物

？都不是，它是鐵和錳！鐵和錳是植物所需的重要養分，在水族箱中卻很缺乏，所以必須一直循環利用。在添加鐵肥料后的兩三天里，盡管有再循環

利用的過程，水族箱中的鐵含量還是會表現出一定量的減少，對于錳的含量也有類似的現象。那么這些鐵和錳元素到哪里去了呢？答案就是過濾器里

淤積的褐色泥狀物質了。為了證明這一點，將淤泥物質溶解在化學藥劑中，并從中檢驗到了大量的鐵錳元素。盡管現在已經采用鰲合（對鐵錳添加一

個保護層）的鐵錳肥料以避免氧化，然而鐵合錳仍然會沉積在過濾器中，因為細菌非常迅速地破壞掉鰲合形成的保護層，鐵錳又被氧化并以褐色淤泥

形式析出。

?

????? 附上原文吧，有興趣的可以看看。有意見的可以提。
????? Why is filtration necessary?
????? Aquarium water ages because organic matter originating from decomposing
????? food residues and metabolic products of creatures and plants accumulates.
????? In the course of time the accumulation of this waste impedes the
????? biological development of the aquarium, plant and fish growth deteriorate.
????? If too much waste accumulates this may lead to toxic effects.
????? "Self-purification of the water" is an expectation that modern aquariums
????? with their dense population and the resulting feeding requirements
????? definitely cannot fulfil. Filtration tries to delay this process. In
????? addition to this important bio-chemical task the filter must also provide
????? optically clear water by removing leaf fragments, floating particles and
????? minute substances.

????? An attempt at collecting all pollutants by purely mechanical means with a
????? very fine-pored filter (somewhat like a percolator filter) has very
????? limited prospects of success.
????? Only relatively large floating particles such as leaf fragments or food
????? flakes can be removed. If the water were to be cleared of floating
????? particles by such a method, the pores of the filter would have to be no
????? larger than a maximum of 0.0005 mm. Due to the filtration resistance such
????? a filter would become clogged almost at once.
????? For the retention of all floating particles the choice of pore size would
????? have to allow the trapping of all particles larger than the wave-length of
????? light. This explains why even extremely thick wadding filters cannot
????? remove turbidity.
????? So how can aquarium filters purify the water and retain minute particles
????? although the pore width of the filter material is several millimetres? It
????? definitely cannot by a mechanical, but by an electro-chemical function. On
????? the surface of the filter medium protein particles (size 0.001 - 0.00001
????? mm) change their electro-chemical properties. They lose their solubility
????? and settle on the surface of the filter medium. Further protein particles
????? follow, covering the filter medium with a protein layer.
????? This protein coating is highly adhesive and retains even fine particles.
????? This explains why the filtration performance of new or freshly cleaned
????? filters is not satisfactory. The adhesion does not become effective until
????? after a few days, when sufficient protein has settled. If attempts at
????? combating turbidity by cleaning the filter are made too soon the adhesive
????? coating is destroyed and the aquarium remains turbid. Frequent exchange of
????? the filter media also results in turbidity. The larger the surface of the
????? filter medium, the better the adhesion for fine particles. However, too
????? coarse a structure of the filter medium impedes the desired adhesion,
????? therefore clay pipes are not very suitable. Very good results are achieved
????? with Ehfisubstrat. Then bacteria begin their work of degradation. Bacteria
????? feed on the partially degraded proteins (amino acids), and after oxidation
????? they release lower-energy metabolic products, which, in turn, serve as
????? food for other bacteria.

????? The main components of organic pollution in the aquarium water are various
????? kinds of protein degradation products. This organic matter is mineralised
????? into an-organic compounds. As a result, there is enrichment with
????? an-organic matter (example: nitrate, phosphate), which is physiologically
????? far less harmful than their previous stages (ammonia, nitrite). Fish can
????? tolerate it in much higher concentration.

?

????? A simplified description of this "mineralisation" is as follows: Protein
????? is broken up into polypeptides, then further into amino acids. These are
????? further separated into ammonium/ammonia (depending on pH value) and carbon
????? dioxide. This is followed by bacterial oxidation by means of bacteria, via
????? nitrite to the final product nitrate. This is an incredible process:
????? unfortunately it has a great disadvantage: it cannot work properly without
????? a sufficient amount of bacteria.
????? When a new aquarium is set up, bacteria are introduced together with the
????? material, equipment etc. Unfortunately they cannot fully perform the
????? process described above because in the early stages their number is too
????? low. In favourable environmental conditions bacteria propagate very
????? quickly. Propagation by division may happen every 20 - 30 minutes.
????? However, it will take at least 3 - 4 weeks until a filter can degrade all
????? occurring substances, and the aquarium should not be stocked with fish
????? before the end of this waiting period. What is the reason? As described
????? above, amino acids are broken up in two stages, via ammonium / ammonia to
????? nitrite and then to nitrate. Two decisive groups of bacteria, nitrosomonas
????? and nitrobacters contribute to this process. When the protein degradation
????? begins, large amounts of ammonium / ammonia are released which the
????? bacteria group of nitrosomonas gradually convert intro nitrite. It takes
????? about 20 days for the nitrosomonas to propagate sufficiently to convert
????? ammonium/ammonia immediately. At this point the bacteria group of
????? nitrobacters have no incentive for propagation because there is no nitrite
????? for nutrition yet. Only when supplied with nitrite by the nitrosomona
????? bacteria do the nitrobacters begin to propagate and to convert nitrite
????? into nitrate. This process takes about 20 days. Therefore, the propagation
????? speed of the bacteria groups of nitrosomonas and nitrobacters determine
????? the "running-in time" of a filter of approx. 3 - 4 weeks. Introducing
????? previously used filter medium can speed up this process. However, this is
????? only a small, if important, sector in breaking up protein products. From a
????? chemical point of view protein consists of carbon, hydrogen, nitrogen,
????? sulphur and phosphorus. During degradation these individual components
????? produce carbon dioxide, water, nitrate, sulphate and phosphate.

????? To avoid a permanent increase of these final substances in the aquarium,
????? the regular exchange of (parts of) the water is absolutely necessary.

????? What does the dirt in the filter consist of? In all aquarium filters you
????? find brown sludge. Is this a combination of food particles, residual
????? faeces, or deposited protein? - No. Iron and manganese, two important
????? plant nutrients, are scarce commodities in the aquarium; they have to be
????? re-fertilised all the time. When the iron value is determined 2 - 3 days
????? after the addition of fertiliser, this will show a decrease despite
????? re-fertilisation, and the same applies to manganese. Where have the iron
????? and the manganese gone? The answer lies in the brown sludge in the filter.
????? For measuring purposes, the sludge must first be dissolved chemically, in
????? the proof iron and manganese will be found again in profusion.
????? Although chelate (a protective coating for iron and manganese) is nowadays
????? added to the fertilizing substances in order to avoid oxidation, iron and
????? manganese are deposited in the filter. The bacteria destroy this chelate
????? coating comparatively fast, iron and manganese can again react with oxygen
????? and are deposited as a brown "sludge".

?