Here’s where it gets a little complicated and where most people get confused, so let's see if I can make this as painless as possible. All new tanks go through what we call a cycling process. During which the first two weeks, after adding fish to the tank, you will see a rise in ammonia from fish waste and any uneaten food. This is an invitation for ammonia-consuming bacteria to come in and set up home. In the meantime you will notice that the water gets a little cloudy, which is a good indication of the presence of bacteria. After about two more weeks the ammonia-consuming bacteria produce nitrIte's which invite nitrIte-consuming bacteria to move in. Now ammonia and nitrItes are dangerous to fish, and will cause disease and eventually death if the levels become too high. If the ammonia and nitrIte levels go above .25 then you need to do a water change to keep them down. In a short period of time the nitrIte-consuming bacteria will produce nitrAtes, which are pretty much harmless to fish as long as the levels don't skyrocket. And, what I mean by skyrocket is that if the test result isn't on your chart then chances are it's way too high. You can keep the nitrAte levels down by doing water changes and by adding live plants to the tank. Once your ammonia and nitrIte levels test at 0 then your tank is cycled. This whole process takes about 6 weeks to complete.

So here’s how the six week Nitrogen Cycle works in brief:

• Fish produce ammonia.
• Ammonia consuming bacteria produce nitrItes.
• NitrIte consuming bacteria produce nitrAtes.
• Plants consume nitrAtes.