I am also unfamiliar with this setup; I read through the pages you linked but no where does it explain how this is different with respect to the biological nitrification cycle and bacteria, so I must assume it is the same as other aquaria. I am naturally skeptical of any product that claims to short-cut nature, so I must assume the bacteria cycle will develop and remain in this as in any aquarium.
Without live plants, it takes 2-8 weeks normally for the nitrification bacteria to colonize an aquarium. If you read the sticky article by iamntbatman on cycling you'll understand the process. This happens in your aquarium as in any other. http://www.tropicalfishkeeping.com/f...m-cycle-38617/
The biological supplements, like Stability I mentioned or StressZyme, add live bacteria to jump-start the cycling process. There have to be fish or some source of ammonia in the tank or this is wasted. Bacteria need food, and for nitrosomonas bacteria ammonia is the food; they convert it to nitrite, then nitrospira bacteria appear and use the nitrite and nitrate is produced; partial water changes keep the nitrates within reasonable limits. So using Stability when fish go in the tank will add a colony of bacteria that will multiply as ammonia is produced by the fish. The bacteria always exist at the level necessary to handle the ammonia and nitrite respectively. If ammonia increases, nitrosomonas bacteria multiply (within 9 hours); if it decreases, the bacteria die off.
As this is a 16g aquarium, I would add 2-3 small fish like danio, wait a few days, then add 2-3 more. This allows the bacteria to multiply in proportion. Use Stability for the week.
On danios, they are shoaling fish which means they prefer to live in groups and will be less stressed in a group rather than 2 or 3 fish. Each species requires a group, so given your 16g aquarium I would say 5-6 of one species, plus perhaps some bottom fish for contrast? Or depending upon what you like.