Chemistry and the Nitrogen Cycle

Couple of post back I was discussing about the prawn and the nitro cycle and its time i continued the story. I left off in stage one of the nitrogen cycle where bacteria will start chowing away the ammonia. So what happens after? Well the bacteria do not really eat away the ammonia and the term use to describe it is that the bacteria converts ammonia into nitrites or NO2. After more than a week, i did a NO2 test with the aquarium water this morning. A sample of aquarium water is collected in a test vial and subsequently chemical reagents are added to it. The aquarium water will then take on a color indicative of the NO2 levels in it. This color is matched to a chart from which a numerical value can be derived.

From the chart we see that NO2 levels are in the 0.3mg/litre range. In my past experience I usually manage to maintain NO2 levels below the 0.3 mark but this is still in the aquarum's early stages so we shall wait and see. Nitrites when present in concertrations above 1.6mg/litre can be harmful to fishes so its best to keep it as low as possible.

On the other hand, this is not entirely bad news because it means that stage 1 bacteria are successfully converting NH3 NH4 into NO2! The stage 1 bacteria are growing! What happens next? thats stage 2 of the nitrogen cycle and this is where another kind of bacteria will convert the nitrites into something else but that's another topic for another time.