There are many types of pumps and filters available for sale in the aquarium trade. You must choose one that is most suitable for your purpose and not the most expensive. If you are keeping Koi or goldfish, you will need a more elaborate system than if you are only keeping a few guppies. Whatever system you select, you must bear in mind that your duty is to give the captive fishes a system that is closest to their natural habitat.
Air pumps, such as power pumps, overhead pumps, vibrator pumps, and piston pumps, are used to pump air (atmospheric air) into the aquarium. Those pumps that pump water into the aquariums or ponds are not normally used in the home aquariums. For home aquarium use, the most popular types are the power and vibrator pumps. Use the power pump with a high capacity filter for bigger aquarium and for fish that by nature produces considerable quantities of waste — goldfish and Koi are typical examples, especially when they are overfed.
Use the double vibrator pumps with the most numbers of controllable outlets you can find for your aquarium. The more outlets you have the more flexibility you can get for driving more aerating stones and the different types of ornamentals.
(ii) FILTERING SYSTEMS
A small inside filter such as a corner or box bubble filter will serve the purpose for a small aquarium of about 10-gallon. To improve filtering efficiency you may use more than one box filter or a bigger-sized box filter in the same aquarium. For the bigger aquarium — about 30 gallons and above, use under gravel filters (also known as biological filters) if your main interest is keeping all sorts of small sizes tropical fishes. Use suitable gravel for your under gravel filters and choose the right type of plants. Use pebbles with coarse sand for most acid and soft water fishes. Do not use marble chips or coral sand unless you are keeping hard water and alkaline-loving fishes or marine fish. If you prefer bigger fishes (more than 3 inches) such as goldfish, Koi, Oscar, or cichlids – it is more economical to use several box filters in one tank without gravel or plants. Most bigger fish uproot plants for fun while some enjoy eating and nibbling them. If you like to plant your aquarium please check the habits of your fish with the experienced hobbyists or refer to aquarium books before you start.
Other types of overhead filters come with small size suction pumps that pump water to the top of the tank and allow water to filter through by gravity force are the efficient combination for use in a small aquarium with less than 10 gallons of water.
When you have a bigger aquarium of 20 gallons or more, overhead filters are not the best choice. The filtering media become choked up easily and overflow all over the floor while the pump burnt out whenever you forget to check the water level of the aquarium. The outside filters, whether power or air operated, are also very popular but you have to check the filtering media regularly; otherwise, you will have to mop the floor daily.
There is another popular filtering equipment, which is actually an electric pump combined with built-in filters. These pumps are specially made for use inside or outside the aquarium. With proper attachments, the cleaning of pumps and filters is neat and non-messy. Some good-quality external or internal power filters such as the Eheim or Vortex series are very efficient but costly.
Be careful if you intend to use Nitrifying bacteria for your biological systems. These live nitrifying bacteria, some marketed as ‘enzyme’ are already dead even before they reach your tank, especially the liquid form. Commercial preparations of nitrifying bacteria often fail because they are sold well beyond the expected shelf life.
However, if you insist on using the nitrifying bacteria, buy the powder form with expiry date indication from reputable aquarium shops. Please remember that even the best quality liquid type has less than one-year shelf life (most have an only six-month shelf life). The biggest users of these products are the aquaculture companies (breeders of food fish, prawns, eel, etc.); water and sewage treatment companies but not the aquarium trade.
Your properly set up tank with stabilized, matured and correct filtering media may contain more bacteria than the bottle you pay at a fantastic price.