The air pump is an electrical device (220v) that produces airflow and is
directed into the aquarium through a hose. At the end of the hose, inside the fish tank you have an
air rock that allows its exit by forming fine bubbles. These bubbles are meant to oxygenate the
Most internal filters come with a hose that introduces water (fine bubbles) into the aquarium
and this way the necessity for an air pump decreases.
Without a filter, the aquarium pump is the only thing that will keep the fish alive for any
length of time without the necessity of changing the water daily.
If you are not in a position to buy a mechanical filter, you can create your own biological
filter by using an air pump and a sponge. The sponge will be kept inside the fish tank and will serve as a “house”
You can achieve biological filtering through the ammonia-consuming bacteria and it is based on
breeding this type of bacteria to filter the water.
There are some types of bacteria that progressively divide the ammonia into its' less toxic
components, nitrates and nitrates.
These components are considered to be non-toxic and you can find plenty of them in nature. In
presence of ammonia and oxygen they tend to multiply. Bacteria attack the aquarium, rocks, sand and even the
Remember that we haven't mentioned anything about mechanical filtering because this one requires
just a surface on which ammonia can settle and well oxygenated water.
If you decide to limit the number of fish due to the biological filtering capacity you won’t
need a mechanical filter.
In recent years, a large variety of new biological filters have appeared. They can increase the
bacteria colonies’ capacity to filter the aquarium water. Actually these filters offer a bigger surface for the
bacteria colonies to breed and provide a bigger amount of oxygen in the water.
Ammonia comes straight from fish’ branchies, from their excrement and also from their food. If
we are able to mechanically filter the solid excrement and their food remains before they decompose we can already
be talking about a major advantage.
Mechanical filtering collects the excrement and food remains from the aquarium but cannot handle
the ammonia problem.
A regular mechanical filter cannot avert both the algae and the small bacteria from the water
nor the solid remains grasped by gravel, plants or even decorations. To avert these solid remains from all areas of
the aquariums it is necessary that we use different methods.
One of the easiest is vacuuming the sands/gravels surface with a hose when you do your
periodical change of water. Exceptions in this case are the marine aquariums that have living substratum.
You can choose to install circular aquarium pumps also known as wave generators which improve
the chances of collecting the remains in the mechanical filter. A filter with a small filtering port collects small
parts but it can also clog easily, so the rule in this situation is that the bigger the filtering port is the
harder it is to clog.
As the filter gets dirtier it is less likely to be able to vacuum any large particles. When this
happens, you know you need to clean your filter.
Bear in mind that a good mechanical filter is one that can retain enough solid elements that it
can maintain clear water without clogging too often.