Aquarium water filters
Aquarium filtration is the most important part of any fish tank. The purpose of aquarium filters is to remove toxic compounds from water. But not everything can be done by filter. You will also have to change water sometimes. That will minimize nitrate levels. This article should help you to understand the basics of freshwater aquarium filtration. You will learn how aquarium filters work and you should be able to decide which types of aquarium filters are best for your fish tank.
Aquarium filtration system
Todays tank filters usually provide three types of filtration - mechanical filtration, biological filtration and chemical filtration. Mechanical filtration is process that removes solids from water. The water passes through filter media where fish waste, pieces of plants and other solids are traped. Mechanical filtration is before biological part. It's necessary to clean the medium so the water can pass through properly to the biological medium. Biological filtration is essential part of filtration system. Filter medium is occupied by beneficial bacteria, which decompose toxic ammonia to nitrate which can be reduced by water changes. Ammonia comes from organic materials like fish waste or food and is dangerous for fishes. Chemical filtration consists of media usually carbon which absorbs metals, chlorine, medications and other impurities from your fish tank. Chemical filtration isn't always included. Mechanical and biological filtration system is a minimum for clean and clear water.
Types of aquarium filters
Market offers many different types of aquarium filters. Let's compare filters for aquarium and have look at their advantages and disadvantages.
Aquarium sponge filters
These filters are very simple and cheap. They consist of sponge and air pump. Sponge filters provide mainly biological filtration and mechanical filtration too. Sponge is an excellent place for colonies of beneficial bacteria. They are used in fry fish tanks or hospital tanks, because they cannot harm the fry and don't remove medication. They aren't very silent filters because of air pump.
Undergravel aquarium filters
Gravel filters are placed under aquarium substrate. Very good biological is provided as the water goes through gravel with beneficial bacteria. Mechanical filtration is poor and under gravel filter provides no chemical filtration usually. It isn't recommended to use this filter in planted aquariums. Maintenance is quite difficult. You can find much better solutions than this type of filter.
Aquarium power filters
These filters are the most used filters for smaller aquarium under 25 gallons. Power filters provide all three filtration systems - mechanical, biological and chemical. They can be external or internal. Internal aquarium filters are quiet and save space behind the aquarium. External filters are easier to maintain and don't disturb the look of your fish tank. External power filters hang on the back wall of aquarium.
Aquarium canister filters
Canister filters are used for large aquariums. It's external filtration with a canister hidden somewhere in aquarium stand. The biggest advantage is the size of canister. It can contain a lot of filter media, so the quality of filtration is excellent. As it is external, cleaning filter is quite easy.
Choosing filter
When choosing filtration for your tank, consider the size of aquarium and the number of fishes you're going to have. Manufacturers tell how many gallons per hour can be filtered. The power of filter should be the same with the size of your fish tank. For example if you have 30 gallon tank, filtration should be able to filter 30 gallons per hour. More power wouldn't be good for plants or fishes that don't like too much of water movement.
