There are many names for the nitrogen cycle: the biological cycle, the nitrification process, the start up cycle, or new tank syndrome.
In essence, the nitrogen cycle is the process of converting ammonia to nitrite and nitrite to nitrates and the establishment of good bacteria in the aquarium and filter. Both of these processes are essential to a healthy tank environment.
It can take two months or more to complete the nitrogen cycle! The process doesn’t always take that long, and there are some tricks you can use to speed things up, but it can be a very long and patience-trying process. You really don’t want to add fish to your tank until you’ve completed the nitrogen cycle — your fish may not survive the process. Both ammonia and nitrites can be very deadly to your fish.
During the nitrogen cycle, you’ll need to test your aquarium water every other day. First, you’ll see ammonia levels rising. After a week or two, you’ll start to see ammonia levels going down and nitrite levels rising. Another few weeks will have the nitrite levels going down and the nitrate levels going up. When your water tests show no ammonia or nitrites in the water (but nitrates are present) you’re finally ready to add fish.
Some aquarium owners start the nitrogen cycle with fish in the tank — but many aquarium experts don’t think this is the best way. The exposure to ammonia and nitrites while the tank cycles can be dangerous, even deadly to your fish. In general, you don’t even want to buy fish until you’ve cycled the tank. However, some hardy species (like the zebra danio) can tolerate the nitrogen cycle better than others.
If you’re looking to get into the tropical aquarium hobby, stay tuned. We’re going to take a look at how you can start the nitrogen cycle, and what will happen in each step.