What is filtration and why do we need it?

Imagine you lived in a room that was the size of your average lounge. Imagine then that you were never allowed out of that room. Then imagine what it would be like if you had to go to toilet in the room and had nowhere to put it. Not a very nice thought is it? How long would it be before you became ill if you had to live like that? That is exactly what it would be like for a fish that has no filtration or no maintenance was performed on your aquariums. Again, it wouldnt be long before our fish became ill and eventually died. So thats why we need filtration. Filtration is the act of filtering water, cleaning it. Humans do it on a huge scale everyday to produce drinking water. But how do we filter our tank water. It is done using various products which can be bought at your local fish shop or you can make your own. But how does a filter work. Most rely on pumping water through some sort of media which cleans the water as it goes through. How? Well lets start with the larger particles of waste that we see floating around our tank from time to time. As the water is drawn through the filter the particles that are suspended in the water are also drawn through the filter. They can be filtered out with the use of filter floss and this is called mechanical filtration where the particles are trapped because they are to big to pass through the filter floss. Once caught in the floss they are broken down by biological filtration. Biological filtration takes place when beeficial bacteria build up on the surface area of your filter media and convert ammonia waste into nitrite which is in turn converted into nitrate. This is called "The Nitrogen Cycle" Finally the third is chemical filtration. This is the use of chemicals to help filter the tank and can be in the form of ammonia remover, nitrate remover or some other chemical which may alter the make up of the water. Most shop fitration is equipped now to deal with all three of these having various compartments in them for different medias. They normally consist of a fine material to trap the waste and then filter media in the form of ceramic nodules gravel or anything upon which the bacteria can grow. Any media that has a large surface area is ideal and there lots on offer at stores. Finally the chemical and these normally come in little bags of say ammonia. So when we look at our tank we have to realise that one of the most important parts of the tank is invisible to us, the bacteria although invisible to the naked eye is at work 24/7 in your tank.