Reef Aquarium Filters - Mechanical Filtration Explained
Reef Aquarium Mechanical Filtration Overview
Filtration is the process of removing solid particles from
aquarium water by some method of straining. This is mostly
accomplished in the reef aquarium by a pre-filter on the
overflow of the tank or by filter floss in the sump or wet-dry
filter. Although mechanical filtration does not remove ammonia,
nitrite or nitrate directly, it can remove the contributors to
these compounds (i.e. biological waste, un-used food).
Fine and coarse foam, filter bags and filter floss are the most common types of material used in the reef aquarium to accomplish mechanical filtration. For easy reference we have separated the filter materials below in a list to explain each of them and how they might be used.
Foam Filters For Reef Aquarium Filtration:
In a reef
aquarium, you will almost certainly see a cylindrical foam
filter on the overflow of the tank as well as one or more
somewhere in the sump, refugium or wet-dry filter. The idea
is to filter out any solid material from the water before it
reaches the biological or chemical filtration media. As the
biological and chemical filtration media works to remove
organic and chemical compounds on a microscopic scale,
dumping large amounts of coarse material would only clog the
filters and reduce their efficiency.
Foam filters come in a variety of densities which give each of them different properties. Coarse foam filters strain out large pieces of material and tend to clog at a slower rate than fine foam filters. The coarse foam works well as a pre-filter, catching large pieces of food and waste material; however, it falls short if needed to filter fine material.
Filter Bags For Reef Aquarium Filtration:
bags are mostly used in refugiums as pre-filters, but they
can be used in any application where there is a place to
mount them. The point is, as the name states, to have a
porous material in the shape of a bag that can be fitted to
piping and provide filtration “from the inside
The perfect application for a bag filter is where an overflow enters a sump, refugium or wet-dry filter. A bag filter can be fitted over the overflow pipe to catch material before it moves into the biological or chemical filtration media. Bag filters come with smaller mesh than most other filter types, so they must be cleaned often.
Filter Floss For Reef Aquarium Filtration:
floss comes in sheets that are sometimes called filter pads.
They come in various densities, thicknesses and colors. The
most common form of this media is the multi- density pad
which is used in wet/dry filters before the water trickles
onto the bio-balls. This pad usually comes in white and blue
coloration as the different colors represent varying
densities of the floss. The white floss is very coarse and,
thus, traps larger pieces of material whereas the blue fiber
is very dense and filters out finer pieces of material. When
you use multi-density floss, be sure to put the less dense
material upstream of the denser to aid in even dispersion of
the water, preventing premature material