The filter system is an important part of the biological purification of the aquarium. Bacteria convert fish waste and plant debris into water-soluble products. Purifying bacteria in the substrate convert food waste and decomposed plant parts into ammonium/ammonia (NH4/NH3). This happens in the presence of oxygen.
In the biological filter, ammonium and ammonia (NH4/NH3) are converted into nitrites (NO2) and nitrites into nitrates (NO3). This process is called nitrification, and for the bacteria (genus Nitrosomonas –
convert ammonium/ammonia and genus Nitrobacter – process nitrites) to perform it, they need oxygen. Sera nitrivec contains millions of living bacteria => The nitrates and phosphates formed in the penultimate phase of this process serve as food for plants, thus closing the nitrate cycle. Nitrate cycle = food and plant remains => ammonium/ammonia => nitrites => nitrates + phosphates => food for plants. If the nitrate cycle does not work effectively enough, fish and plant waste accumulate and slowly poison the aquarium water. To eliminate a large amount of waste products, it is necessary to plant as many plants as possible (especially for a new aquarium), which will also prevent excessive algae growth. The fish-plant ratio is very important for biological balance. Usually, in an aquarium, plants cannot destroy all the waste products formed by fish. Therefore, it is important to ensure good biological filtration, and periodic water changes should not be neglected. It is recommended to change 20% of the aquarium water every week.
The bacteria that carry out the nitrification process need a substrate to live in; they cannot live freely swimming in water. Therefore, it is important to use biological filter media for filter filling.
The highly porous Sera Siporax ® provides the largest possible surface area for the development of nitrifying bacteria. Its pores are of optimal size for the development of nitrifying bacteria, so they can grow on the pore walls without clogging them. Sera Siporax ® is so porous that it provides 34 times more surface area for nitrifying bacteria than conventional ceramic filter material. Thus, one liter of Sera Siporax ® provides 200 liters of purified water. This material is very suitable for small-volume filters. Since usually in an aquarium the fish/plant ratio does not usually ensure the destruction of all accumulated nitrates, their degradation by bacteria is necessary. Sera Siporax ® provides enough space for the development of bacteria and food for them, but deep within its pores, there is a small inflow of fresh, oxygen-rich water. This forces some bacteria to break down nitrates to obtain oxygen. Thus, they reduce the amount of nitrates in the aquarium. One liter of Sera Siporax ® provides a useful surface area for the development of purifying bacteria equal to that in 34 liters of conventional ceramic filter material.
Compared to ceramic materials offered by other companies, Sera Siporax ® not only has a large surface area but also the necessary dimensions and shape. If we crush the rings of Sera Siporax ®, we will get many times more surface area for beneficial bacteria in one liter of filter material, and it will take up less space in the filter. Is this the most important thing? Besides a colonization surface, beneficial bacteria also need oxygen. If the filter material is too dense, it will easily clog, and no matter how much surface area it offers in its pores, it will not be effective enough. Sera Siporax ® is in the form of a ring, which prevents dirt retention and ensures a fresh flow of oxygen. This is why Sera Siporax ® is one of the most highly effective ceramic filter materials for bio-filtration.
The speed of water movement in the filter (flow rate) also matters for good filtration. In a new aquarium, the water speed is higher, which prevents bacteria from settling in the pores of the filter material. It is necessary to reduce the speed (with Sera fil, it can be reduced by carefully turning the stopcock according to the instructions in the manual) in the initial stage until the nitrate cycle is activated. This will allow the bacteria to attach more easily and begin to multiply. After this stage, the filter flow rate can be slightly increased.
