If you have 0=ammonia=nitrites, and more than 5ppm in nitrates, your cycle is fine. You can test the water prior to adding Paraguard each day to make sure you do not have ammonia or nitrites. Nitrites are easy to protect against with salt. Ammonia would have to be dealt with using Prime or other water conditioner to bind the ammonia for 24 hours. You should not dose with Paraguard if you have added a water conditioner to your tank less than 1 hour prior.
If you decide to go the Paraguard route, I would do at least 25% water changes every 3 days.