Email Sign-Up Go to Shopping Cart (0)



Customer Service

Biological Media: Balance and Detoxification

Drs. Foster & Smith Educational Staff
Aquarium Filter Selection Guide 
Biological Media: Types & Benefits 
Chemical Filter Media Selection Guide 
Filters & Filter Media
Poly Filters
Poly Filters
As low as $6.99
Drs. Foster and Smith PhosPure Pads
Drs. Foster and Smith PhosPure Pads
As low as $8.99
Hydro-Sponge Pro Filters
Hydro-Sponge Pro Filters
As low as $7.99
Introduction to biological filtration

Biological filtration is the action of nitrifying bacteria breaking down dangerous ammonia, converting it to nitrite, and then converting nitrite to less toxic nitrate.

Biological media is any inert material that houses the beneficial bacteria colonies that break down ammonia to a less toxic form. Biological media is normally placed in your filtration system where water is forced through, bringing nutrients and oxygen required by the bacteria to complete the nitrogen cycle.

A variety of media is available for bacteria cultivation. Small biological media, such as Fluval BIOMAX Filter Media, Azoo Bio-Glass, or Eheim Substrat Pro are an excellent option if you have a small aquarium. They are extremely porous and boast incredible surface areas. Plastic media, such as BioMate or Coralife Bio-Balls do not have the extensive surface area, but they are unlikely to clog and never need replacing. Bio balls also work to degas ammonia before bacteria break it down, lessening the load on the filter.

When starting a new aquarium, a great source of bacteria is a scoop of surface gravel from an established healthy aquarium or some bio media from a healthy filter, as long as the aquarium hasn't been treated with medications or other chemicals. Other good choices include porous biological media, or a bacteria additive like Drs. Foster and Smith Live Nitrifying Bacteria or Special Blend.

Check your filter regularly to ensure debris are not clogging biological filter media and decreasing efficiency. For nitrifying bacteria to thrive, they need oxygen and ammonia or nitrite. Biological media should not be replaced unless it has become too clogged to function, and many times can be simply rinsed with aquarium water to unclog. In most cases, it is recommended the filtration system include mechanical media to filter particulate from the water before it reaches the bio media. This will slow the build-up and help prevent clogging.

Once beneficial bacteria are established in your biological media, they are difficult to destroy, except by over-cleaning, using chlorinated water, or using certain medications, such as antibiotics.


Click here for a more printer-friendly version of this article.  
Click here for a pdf version of this article.  


Contact us
8 am - 8 pm CST
7 days a week

7 am-8 pm, CST
7 days a week