| | Re: Seachem Metronidazole
You're welcome. We don't recommend mixing medications, as there is potential for negative drug interactions to occur when doing so. With that said, if you want to try Metro directly in the tank for the time being, then I would recommend doing your best to pre-dissolve it in some fresh water before placing it into the tank; this will help with the solubility issue and will make it more effective.
Once your PolyGuard arrives, I would wait 24 hours after your last dose of Metronidazole to begin treatment. When used as directed, both of these medications are safe for scaleless catfish.