Join Date: Jan 2009
Location: Pinellas Park, FL
Did you try "seeding" the new filter with filter media from an already establish tank to expedite the nitrogen cycle ? It can be as simple as placing some of the "old" filter material inside the new filter or directly into the the tank, also using some tank gunk or mulm will help.
Another option if adding products like cycle, stress zime, etc.
From personal experience I will advice against 100% water changes, this definitely upsets your newly setup bio system. I will suggest 25% daily change for at least 7 days and you should be good by them.