You Are At: AllSands Home > Pets > Fish > Fish tank filters
One of most important things you need to consider when setting up a new
tank is the filter you are going to install. For some types of exotic fish,
the wrong filter means death. You will need to understand what a filter is
and how it works before you purchase one for your tank.

How do they work?
A tube suctions up air which forces water to enter from the tank. The
water transfers through the filter and back out into the aquarium. Filters
vary on design but,
this is basic concept found in all of them.

Why is a filter so important?
Filters basically perform two important duties. The first thing they do is
remove all harmful and/or unneeded particles from the water. The second
thing they do is to reduce the amount of ammonia in the tank.
The filter needs to be changed occasionally, at least cleaned. The
particles it removes from the tank stay in the filter and the water that
passes through will eventually carry it back into the aquarium.
With a reduction of ammonia in your tank, there will be a lower chance of
algae growing in your tank.

What kind of filter should you use?
There a few things that will determine what kind of filter you need. These
include the size of your tank, the type of tank, the fish you plan you buy,
and your budget.
The three cheapest types of tank include the corner box filter, under
gravel filter, and the sponge filter. Corner box filter come with most
smaller aquarium kits. This filter provides good oxygen circulation and
ammonia removal.
The under gravel filter works just like its name suggests. Instead of
pulling the dirt particles and ammonia up and out of the water, the under
gravel filter pulls them down under the gravel and traps them there. The
waste and debris are trapped along the length of the bottom of the tank,
keeping the rest of the tank clean and safe for your fish.
The sponge filter is used mostly when there is breeding going on. Since
the tubes on the sponge filter is so small, baby fish will not be sucked up
into it. Besides, the sponge filter provides microscopic nutrients for
young fish.
Then there are more expensive filters. These include canister filters,
diatom filters and reverse osmosis filters. These filters are designed
mostly for larger tanks.
Canister filters a larger amount of water. In addition, they also serve as
a great water softener and degasser. The diatom filter is basically same
except that they provide an added bonus. They use diatomaceous earth,
skeletons of tiny animals that are used to form plankton in both fresh and
salt water tanks. Reverse osmosis filters are basically used for tropical
fish that cannot live in hard water. This filter removes any metals, mineral
salts or calcium deposits that may form in your tank.