George wrote:
"~ jan JJsPond.us" wrote in message
...
Personally I like this website's definition,

http://www.vcnet.com/koi_net/dan.html (bsigh) ~ jan


~Power to the Porg, Flow On!~

It is simpler, but doesn't go into a lot of detail for those who want that
detail. But for the beginner, it will suffice. I like the graph on the web
site I provided because it shows the complete cycle, and shows clearly
where a water change is desireable (although one can obviously do so at a
much earlier time if the need arose).

This is a good page also http://www.pondkoi.com/nitrogen.htm

Read all of the other pages too and then you will have the big picture.