Its good that its reading nitrites - it would read ammonia either way. Are you moving all the fish and the filter over? If so you should be fine as you will have the same bacteria colony supporting the same amount of fish just in bigger volume.
Some extra fast growing plants to start with will help even if you dont use them long term.
Wills
Some extra fast growing plants to start with will help even if you dont use them long term.
Wills