The Nitrogen Cycle
(or what's that smell?)

by Tim Salter

This is certainly not an end all description of the Nitrogen Cycle but enough information to hopefully keep you out of trouble while you make some mistakes because like me you ignored the advice of people who have been doing this for years. (Fishy Business Staff) Also, the nitrogen cycle is not specific to aquariums but is seen in nature everywhere because Nitrogen is essential to all living systems.

Fish produce Ammonia(NH3) as waste. Ammonia is toxic to fish so we can't have that hanging out in the aquarium. That is where bacteria comes in. Some bacteria uses Ammonia as part of their metabolic process. They use up the Ammonia and convert it to Nitrite(NO2). However, Nitrite is also very toxic to fish but another bacteria uses the Nitrite in it's metabolism and converts it to a compound known as Nitrate(NO3). Nitrate is not nearly as toxic to fish. However, we can't let that build up so we keep the Nitrate down by doing regular water changes. Read that last sentence again. You have to do it. If you don't like doing it a lot then put less fish in your tank.

So a few principles to apply from this bit of information.

1. The bacteria we are speaking of is called Aerobic Bacteria because it needs Oxygen to function. So we need to aerate the water well as well as have places for the bacteria to grow. You need surface area which is why things like bio balls work so well.

2. The safe way to get the cycle in your tank working (breaking in your tank) is to introduce a fish or two. Feed the fish, let them produce waste, let the Ammonia build up and then the Bacteria will flourish and remove the ammonia and nitrites. Soon you can add more fish and the cycle can once again compensate. There is a limit though to where the Bacteria can't keep up with the tank and at that point adding fish means you are overloading the tank and that causes all kinds of problems especially if you are not vigilant about water changes.

3. This is almost the same point but I am going to say it again because so many people ignore the recommendations from their local fish store and purchase many fish from day one and then they wonder why they lose them all. Don't put a lot of fish into the tank unless you want to have a huge ammonia build up and lose some if not all of your fish.

So not to scare you but all you need to do is tank your time and introduce the fish slowly and you will be very happy with the results.

Tim Salter (fish enthusiast)