For those of you advanced AQUASCPRs,
The nitrification process requires the use of two distinct groups: bacteria that convert ammonia to nitrites and bacteria that convert nitrites to nitrates. These “group A” bacteria (which generally are either Nitrosomonas, Nitrosospira, Nitrosococcus) bind to the hydrogen in NH3 (ammonia), while also adding oxygen to the nitrogen, thus creating nitrite (NO2). The same is done with the “group B” bacteria (Nitrobacter, Nitrospina, and Nitrococcus), which bind another oxygen atom to the nitrogen grouping. Out of the three nitrogen groupings, nitrate is the least toxic, albeit still toxic. However diluting the nitrate through water changes helps ensure the nitrate never causes a problems.
Nitrifying bacteria once established can double within a day, however starting from a bare tank requires airborne bacteria to convert from being airborne to aquatic, which is what takes so long for the bacteria to establish. The longest parts of the cycle involve the ammonia converting to nitrite and the nitrite converting to nitrate, however once the nitrate is traceable, the cycle finishes quite quickly.
Certain things can affect the speed of a cycle, mainly pH and temperature. With pH, the important thing is to make sure you have a high enough pH to actually start the cycle in the first place. This is because of the way pH works. When the water is below a pH of 7 (neutral), it means that the water is acidic, AKA there are excess H+ atoms floating in the tank. These hydrogen atoms end up bonding with any ammonia, converting it into ammonium. Once converted into ammonium, it no longer is as harmful to fish, however it also does not convert to nitrite either. This will stop the cycle from step one. Temperature is also another factor. Bacteria grow faster in general in warmer conditions, which is also why we refrigerate our food.
There is also another way to reduce nitrogen levels within your tank without water changes: plants. Plants add another component to your tank both aesthetically and biologically. Aesthetically, it is one of the most important factors in aquascaping. Biologically, it sucks up nitrogen for the plant’s growth, allowing for better water quality. While it may seem daunting to grow live plants in your aquarium, many plants are very beginner friendly! Slow growing plants such as java fern and anubias always add a nice touch to any aquarium, and require very little.
Understanding why certain things work in the aquarium leads to a better understanding on how to handle certain problems. While complex information is not always needed, the more you know in this hobby, the easier it becomes.
~Keith Kim, Featured Writer