Principle of activated carbon filtration

The adsorption capacity of activated carbon is related to the water temperature and quality. The higher the water temperature is, the stronger the adsorption capacity of activated carbon will be; if the water temperature is above 30 ℃, the adsorption capacity will reach the limit, and it is possible to reduce gradually. When the water quality is acidic, the adsorption capacity of activated carbon to anionic substances is relatively weakened; when the water quality is alkaline, the adsorption capacity of activated carbon to cationic substances is weakened. Therefore, pH instability of water quality will also affect the adsorption capacity of activated carbon.

The adsorption principle of activated carbon is: forming a layer of balanced surface concentration on the surface of its particles, and then adsorbing organic impurities into the activated carbon particles, the adsorption effect is very high at the initial stage of use. However, as time goes on, the adsorption capacity of activated carbon will be weakened to some extent, and the adsorption effect will also decline. If the water quality in the aquarium is turbid and the organic matter content in the water is high, the activated carbon will lose its filtration function soon. Therefore, the activated carbon should be cleaned or replaced regularly.

The size of activated carbon particles also has an effect on the adsorption capacity. Generally speaking, the smaller the activated carbon particles, the larger the filtration area. Therefore, the powdered activated carbon has the largest total area and the best adsorption effect, but the powdered activated carbon is easy to flow into the aquarium with water, which is difficult to control and rarely used. Granular activated carbon is not easy to flow due to particle forming, and impurities such as organic matters in water are not easy to block in the filter layer of activated carbon, which has strong adsorption capacity and is easy to carry and replace.

The adsorption capacity of activated carbon is directly proportional to the contact time with water. The longer the contact time is, the better the filtered water quality will be. Note: the filtered water should flow out of the filter layer slowly. The new activated carbon should be washed clean before the first use, otherwise there is ink black water flowing out. Before the activated carbon is put into the filter, 2-3cm thick sponge shall be laid at the bottom and top to prevent the algae and other large particle impurities from penetrating. After the activated carbon is used for 2-3 months, if the filtering effect decreases, the activated carbon shall be replaced with new one, and the sponge layer shall be replaced regularly.