Quick rundown on aquarium filter pumps

When it comes to aquarium pump filters, there are a few different types to be aware of before your filter purchase fully meets the needs of your aquarium and it's cute, all be it slimy inhabitants.

The natural waste products come from all living animals - that's pretty obvious. Most critters make their business and then walk away. Some might flush or even clean afterwords if they're human, but sadly, not all will. No problem, you can walk away and the problem is gone. Your aquarium however, is an enclosed environment where there is no walking away.

Fish waste exists mainly in the form of ammonia and excreted solids. The ammonia, if allowed to build up is the more toxic of the two. Biological filters available today can break down the ammonia by means of bacterial action into relatively harmless nitrates. Mechanical filters are generally used in conjunction with the biological type to remove the solid particulate waste, though there are various types of each of these filters.

Chemical filters are another option, though these are generally used only if there is a specific chemical hazard such as dissolved heavy metal salts or any specific medication that has been used for the fish. Generally, aquarium filters are of the biological and mechanical type with the chemical option available if needed.

By far the most common design of aquarium filter these days is the powerhead type. These are available in a number of sizes and have a very simple operating principle, whereby the soiled water is forced through the filtration media by means of an impeller and then returned to the tank. They simply attach to the side of the tank by means of a suction device and are operated by mains electricity.

Powerhead filters generally consist of a mechanical filter and a foam based biological filter where the active bacteria are held in foam pads or wadding, and the filters are easy to clean. Probably their main disadvantages are cost and size. They look pretty ugly inside the tank and can get clogged up pretty quickly if you have a lot of fish. They also create fairly strong currents, so are generally unsuitable if you are breeding since the fry can get caught in the intake.

If you are breeding, (fish that is), then an air powered filter would be better than the powerhead. These filters are fairly simple, and useful for larger solid particles and biological filters. The under-gravel filter is one of the more traditional filter designs, though it takes a fair bit of maintenance. A perforated or porous plate is covered over with gravel that also contains active bacteria for further chemical filtering. It can be very effective if maintained and used properly.

The water is drawn from under the perforated plate by an air pump that causes the water in the aquarium to be sucked down through the gravel. The gravel filters out the solids, and the bacteria convert the ammonia ultimately to soluble nitrates. The filtered water is then drawn up an uplift tube back into the main area of the tank. If more volume is needed which necessitates a more powerful pump, a powerhead or regular centrifugal pump can be used in place of the air pump.

An under-gravel filter should cover the full area of the bottom of the tank, and the slots and gravel size should be properly matched to prevent the gravel clogging up the system by falling through the slots. It is very important with this type of filter that it be cleaned out regularly, about once a month on average depending on size. Use of siphon tube will remove the fine sediment from the gravel. It is not a difficult job, but could be fatal to your fish if you neglect it.

There are other types of aquarium filters that you can use too. External canister filters can be fitted outside the tank. Water is driven through it and then back into the aquarium. The filtration units can be formatted to suit your needs, and designed to hold biological, mechanical and chemical units. They are expensive and only really suitable for the more serious aquarium specialist. If you are new to aquariums, then you will also likely come across the inexpensive corner filters. Be careful with these since they are not really suited to supporting anything but the very smallest tanks.

The sponge filter is a better low cost bet than the corner unit mentioned previously. It consists of a sponge filter through which the water is forced. This not only removes solid debris but also contains bacteria that remove the harmful ammonia. If you are unsure about which type of filter is best for you, then go with the flow (pun intended). Unless you intend to breed small fish the powerhead type of filter is the most popular. Generally external filters are easier to operate and clean than those that operate inside the tank, though much depends on your budget and how much water you need to filter. Hopefully, you now know what you need to know to purchase the best aquarium filter system your your setup.