Protein Skimmer
In a well established tank there is a gradual build-up of waste rail which is not easily broken down by bacteria. This is in the Love albumin, a protein found in egg-white, and can be
When foam develops on the water surface, and the bubbles persist. This is a greasy film of protein and bacteria. The characteristics of this foam serve to help remove it. A simple device called protein skimmer can be used occasionally. Powered by a bubble airlift, the skimmer is suspended in the tank. An aeration stone at its base produces foam, which can be.
Nether device used by some aquarists is an ionizer, which generates ozone and diffuses it into the tank water. This has an antiseptic action, killing bacteria and other organisms, and also speeding the breakdown of nitrites. If used to excess, however, twill kill the beneficial bacteria in the filter bed, and, as ozone is an irritant, may damage the fish. This is an expensive device and needs to be used very carefully if it is to give good results. Some aquarists use an ionizer instead of a biological filter.
A similar device is the ultraviolet sterilizer, which draws tank water through a powerful source of ultraviolet radiation, killing micro-organisms. This does not damage bacteria in the filter bed, but probably does not kill many disease-producing bacteria either, as they are exposed to the radiation for only a short time.
Yet another hi-tech gadget is the diatom filter, used in conjunction with a high-output power filter. It is a special filter cartridge containing a material consisting of the skeletons of Diatoms, which are microscopic marine organisms. It is so efficient that even single-celled parasites can be filtered out of the tank water, but because of its tremendous efficiency the filter medium becomes blocked very quickly, and the system needs constant maintenance.
For the average aquarist, a biological filter and an ordinary power filter are quite sufficient for effective filtration, and require the minimum of upkeep.