The Nitrogen Cycle

Since we know where ammonia comes from (protein by-product and is excreted mainly through gill membranes and waste that is decomposed by other microscopic organisms), then we could start talking about the nitrogen cycle. It is again, I need to reiterate this, a recycling process of the nitrogen.

The nitrogen cycle is simply not as simple as presented in most online source pertaining to fish keeping. It involves a multitude of pathways (or processes) which are often not put into detail. The typical presentation is that of ammonia, nitrite and nitrate as a non-reversible 2 processes, one followed by the other....

Ammonia, which will impede oxygen exchange in the gill membranes, once present in the water is converted to nitrite by a population of bacteria. Nitrite which is more toxic (related with oxygen transport in fish blood) than ammonia is then converted by another group of bacteria into nitrate (ill effects takes a longer time to manifest, in short it won't kill your fish immediately unless the levels are really high).

The two processes is a means of simplifying the 'cycle' but the finer details one needs to know here is how long it takes to achieve the conversion of the substances involved and how fast the two groups of bacteria to populate the filter media.

In reality, it is reversible in a sense that there are other pathways that can convert the nitrate back to ammonia but that will not be our main concern here, we are after all sticking to the basics.

To be continued.....