Biological Filtration

Fluidized Bed Filtration

The successful aquarium is virtually a living ecosystem.  A part of the ecosystem involves microorganisms and chemical reactions.  A sound biological filter is considered by many, the most important filtration system of the aquarium ecosystem.

A biological filter is one that involves the propagation and retention of billions of aerobic and anaerobic bacteria.  Most aquarists pay close attention to the aerobic, or nitrifying bacteria (Nitrosomonas, Nitrobacter).  These bacteria grow in the presence of oxygenated water with a food source such as ammonia (NH3), or nitrite (NO2) present.

Initially, the sound of growing bacteria, and creating a biologically active ecosystem sounds like a complicated process, but it actually is fairly simple with the right conditions, equipment, and animals.

Most commonly, the bacteria are added by simply adding fish.  They hitch a ride on the very bodies, mouths, and gills of fish and other living organisms.  They will drop off the bodies of the fish, and spread throughout the aquarium.  Anywhere there is oxygen-rich water, these bacteria will grow.   The only problem with this process, is that fish also produce ammonia.  In fact, more than the bacteria to compensate for its own waste.  So fish need to be added gradually, because these bacteria can take several months to fully establish.

These nitrifying bacteria consume ammonia (NH3) and nitrite (NO2) to break these common toxic aquarium chemicals into  nitrate (NO3), the final bi-product.   NO3 is then removed either by further chemical processes, or more commonly, by changing out a percentage of the total aquarium water on a regular basis, and replacing with water that is free of heavy metals, and is the appropriate temperature, pH,  and hardness (and salinity in the case of marine tanks.)

There are many types of biological filters out there today, many of which also incorporate other types of filtration.  Some commonly used bio filters include:  under gravel filters, bio wheels, trickle filters, canister filters, fluidized bed filters, sponge filters,  and live rock/live sand  have also become popular in saltwater reef aquaria.

Every aquarium is a different environment, and has has it's own set of demands.  Some filters are better suited for a some aquariums then others. Consult us, or read up on what biological filtration is right for your aquarium system.





Many organisms such as this reef sea slug, sea cucumbers, snails, hermit crabs, and other select invertebrates, help to naturally enhance the biological filter by mixing up substrate, and disallowing the growth of oxygen-robbing algae.





Dwarf Gourami

This family of  fish  live in many parts of the world, and are a hardy, colorful addition to most freshwater community aquariumsFor the most part, the gourami is a peaceful community fish.


Canister filter

Foam Filtration

Power Filtration w/bio wheel

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