Leave him in copper for one more week, so he gets 4 weeks total exposure time. After that, I recommend doing a large WC, running carbon for 24 hrs (in a reactor works best), and then dosing Prazipro.
Technically you can mix Prazi & copper, but I reserve this for emergency situations (when the fish has
both flukes
and ich/velvet) for two reasons:
- The presence of copper diminishes praziquantel's overall effectiveness (but still usually enough to get the job done).
- Mixing Prazipro with any other med increases the chance of a bacterial bloom (cloudy water) occurring, which can starve most of the O2 out of the water and suffocate your fish. This is because the oxybispropanol found in Prazipro doesn't always play well with other meds. This scenario does not usually occur when mixing with copper, but I've seen it happen when mixing Prazipro with CP and antibiotics. One time it happened, and I did not move a CBB into another QT fast enough and lost him.
So, I just play it safe now. 