Nitrogen Cycle

[Wildiana]

what does it mean to do a "Nitrogen Cycle" is this a fishless cycle"

 

[Wildiana]

"unaided by special products" don't understand, no fish, no ammonia added?

 

[cgrabe]

The nitrogen cycle is the voodoo behind converting ammonia into less-harmful products; it's not really something you have to do (see here) but rather something that happens already in nature. A fishy or fishless cycle establishes the bacteria in your aquarium that carry out the conversions. Both fishy and fishless cycling accomplish the same thing; the only real difference is the initial source of ammonia.

What 'unaided by special products' means depends on how it's used in context, but it probably means not using bottled products like Bio-Spira or Cycle.