from another
thread
the nitrogen cycle in a nutshell:
1) ammonia added: throw in some shrimp, some flake food, some uncured rock...
2) nitrosobacter grow: these bacteria oxidize ammonia and turn it into nitrite.
3) ammonia converted to nitrite: after the first bacterial population boom, the ammonia will be converted to nitrite, and the bacteria will starve and populations drop.
4) nitrobacter grow: a second set of bacteria will grow, and break down the nitrites into nitrates.
5) nitrite converted to nitrate: the second population boom will convert the nitrite to nitrate, and these bacteria will decline.
6) cycle basically complete: the end product, nitrates, will build up as the other wastes are broken down, and the two types of bacteria reach population equilibria. once the balance is reached between ammonia production and breakdown, the tank is considered "cycled"
