It seems to me, based on a number of the posts and responses I've seen regarding cycling and the nitrogen cycle in both the freshwater and the saltwater forums that a good number of individuals have some very inaccurate mythconceptions about this process.
First of all, lets talk nitrogen; nitrogen is the most common gas in our atmosphere. It makes up about 78% of air, and in its predominant form of N2,
is not usuable by the majority of living things. However, every single living organism on the planet, both aquatic and terrestrial requires nitrogen. Nitrogen is used to create amino acids, which are the building blocks of proteins. All living organisms as we know them uses proteins to grow and develope. In other words, nitrogen is absolutely essential to your aquarium
That nitrogen is taken up by organisms living in your aquarium either in the food they consume or in one of three other forms: ammonia, nitrite, or nitrate. And all the forms are present in every single aquarium, river, stream, lake and body of water on the planet. The statement that my aquarium has 0 ammonia, nitrite, or nitrate is a misconception based on the results of the "empowered" use of chemical test kits. What you have is not truly zero ammonia, nitrite, or nitrate, but rather undetectable levels of these substances (with your chemical test kit). Every fish in your tank excretes waste every single day and every single plant or algae in your aquarium has leaves or blades that are constantly dying and decomposing. All this waste production and die-off releases nitrogen in one of its forms (typically ammonia) into the aquarium. Bacteria present in the aquarium then convert ammonia into nitrites and other bacteria convert nitrites into nitrates, and it is picked up and used by various organisms within the aquarium. An aquarium with zero nitrogen is quite simply nonexistent!
So why then, when some poor, uniformed soul posts up about cycling their aquarium with living organisms, do hackles rise and member rush to pounce all over said poor, unsuspecting soul who is simply asking how to the right the wrong that they've inadvertently created? Completely incorrect responses like "Everything will Die," "You're being cruel and inhumane", and "nothing can live through the cycle" begin to fly. Totally inaccurate comparisons of smoke filled rooms and toxic chemical baths appear in post after post. The poor besieged OP shrinks back in horror and drifts away to a more informed and understanding site.
Ammonia, nitrite, and nitrate are present in every single body of water on the planet including the very cleanest and most well-kept aquariums on this site and there is nothing harmful or toxic about those substances, provided they are kept at appropriate concentrations. Both saltwater and freshwater aquariums can and are cycled every single day with livestock in a completely safe and humane manner
Soft Cycling the Saltwater Aquarium
Fish-in Cycling: Step over into the dark side - Aquarium Advice
all it takes is a little knowledge and elbow grease!
Over and over I see members of this site saying, "we're just trying to help" and "people need to hear the hard truth in order to understand". Well folks, here is the hard truth, when you tell someone everything is going to die if they cycle with livestock, then you're wrong! If you truly want to help and not drive people away from our site, you need to step up and educate yourself, then you will truly be prepared and able to help others.
Regurgitating myths and mythconceptions simply turns people off and drives them away. In most cases it doesn't save any animals, because very few people ever take something back once they've purchased it. They simply leave and continue in their uninformed state with what they were told to do by somebody else. If you truly want to help, you need to learn to respond with tact and kindness, not rudeness and "hard truths."
A friendly reminder about tact
I'm willing to bet that there isn't a single person on this site that has not made some mistake that has inadvertently led
to the death of some aquatic organism in his or her tank. We all make mistakes and certainly I've made more than my fair share. When we take the time to help other members by responding to their questions, we need to remember the errors that we ourselves have made, step down off our high horses, and take the time to make a little more humble and understanding posts if we truly desire to help.