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(from the filter, or tank substrate) from an established, cycled and healthy fish tank. The cycled media
will aid the transfer of desirable bacteria into the system to colonize the filter.
One way to acclimate a recirculating system with a biofilter is to add a few hardy fish, turtles, or
mollusks to the system. Start off with restricted feeding and gradually increase as the filter develops.
Keep in mind; you do not want to add sick fish, or anything that may pose a disease or parasite risk to
your future inhabitants.
Bead filters will begin capturing suspended solids immediately because that is primarily a physical
process that is not dependent on the development of a biofilm. The biofilm for biological filtration will
take a few weeks to develop if it is not introduced into the system via established media. The
heterotrophic bacteria will grow rapidly and quickly attach themselves to the beads. The nitrifying
bacteria, however, are very slow reproducers and may require almost thirty days under warm water
conditions (2 - 3 weeks is more typical) to establish themselves.
Figure 3
Two specialized types of nitrifying bacteria convert toxic Ammonia and Nitrite to the relatively
safe Nitrate. Bicarbonate ions and oxygen are required in large amounts
.