I'll second MonsterMinis.
Nitrites are only slightly less toxic than ammonia, and need to be kept as low as possible. Further, as long as you aren't doing water changes immediately after dosing Stability, the bacteria have plenty of time to adhere to surfaces and begin replicating.
As mentioned before, your tank is close to cycled as it is, meaning you have a colony of bacteria that has already began to be established, and doing water changes will not effect this.