Power filters are popular filters among casual fish hobbyists, as they are affordable, effective and easy to use. Unfortunately, even the highest-rated models are only appropriate for aquariums of 100 gallons or less. If you need more filtration than this, you will have to opt for a different filter style.
Power Filter Description
Power filters hang partially submerged, against one of the aquarium’s walls. They suck dirty water from the tank and into the unit via an internal, fan-like impeller, pass it through a variety of filter media and pump the clean water back into the tank. Some units have a moving “water wheel” as well, which helps bathe the beneficial bacteria that help breakdown nitrogenous waste products in oxygen.
Power Filter Ratings
Manufacturers rate their power filters according to the amount of water they process per unit of time. Typically, they express this in terms of gallons per hour. Ideally, an aquarium filter should treat all of the water in the aquarium in about 10 minutes. Therefore, if you have a 20-gallon aquarium, you will need a filter that pumps around 120 gallons per hour.
The Right Power Filter for You
Most power filters are relatively easy to use, and installation is straightforward. While all power filters work similarly, some models work better in a given situation than others do. If you have a lot of fish in the tank, a unit with a bio-wheel is a good choice. The amount of sound produced by different units varies considerably; while this may not bother everyone, the hissing, gurgling and splashing sounds generated by louder units may bother light sleepers.
Battle of the Brands
Most major filter manufacturers produce a line of power filters – for the casual keeper, the differences between the brands are minor. Aqueon, Marineland, Tetra and many other companies manufacture models suitable for 40- to 70-gallon aquariums. Most of these filters treat between 250 gallons and 350 gallons of water per hour, but the Marineland 400 has a slightly higher flow rate, and processes 400 gallons per hour. Penn Plax, Danner and Hagen all produce slightly higher rated filters that pump up to 500 gallons per hour, suitable for 70- to 100-gallon aquariums.
When All Else Fails
If you keep particularly messy fish, or have a crowded tank, it may be necessary to upgrade to a canister or wet-dry filter. Some are capable of treating thousands of gallons per hour, and they will quickly clear your cloudy tank. However, these units have their drawbacks: they are more expensive, often loud and more difficult to use and maintain than power filters are.