hi.bought myself a 164l tank, i haven't set it up yet .My wife bought me a 22l tank to start off with ( i know its small),16 by 9 and 10 high.I don't want to loose fish so I'm starting slow with a fishless cycle.i treated the tap water before putting it in the tank. and being feeding the tank for a week now every 12 hours.My nitrite levels are very high.
1.how long before they lower and become nitrates.( haven't done water changes yet)
2.at this stage can i add live plants ( the tank is decorated with plastic ones )
3.when the readings are correct.i want to add the following fish ( not all at once )
These are the groups I'm interested in, not sure which 1 group to choose as they are all good looking fish.is there a small algae eater i can add to a group.

group 1 group 2 group 3
3-zebra danios 2-honey or 2-dwarf gourami 12 assorted tetras ( small ones)
3-leopard danios 4-Cory's
3-pearl danios
i hope that this doesn't overpopulate my tank.
any other group suggestions i can consider.( don't want livebearers )
thanks