If ammonia and nitrites are zero ppm, then adequate bio-filtration. At some point you may remove Penquin or leave it with Aqua-Clear on this tank.
Regarding nitrate levels, I prefer to keep at 10 ppm or less. IMO nitrate at 20 ppm and higher will stress fish. Nitrate is controlled with water changes. If nitrate does not .drop to desired level, then increase frequency or percent total volume of water changed.
Six weeks minimum for new tank for biofilter to be effective. But adding Aqua-clear with fully functional Penqin would be fully functional in much less than 6 weeks.
Like a complete unknown