If u ask me for my noob advise, i will not use rowa, biopellet and refug for fowlr. Just weekly 50% water change is good enough.
For ich, normally 0.3 is good enough.
Copper is a good n bad to fish. If your fish is exposed to copper for too long, problem like hlle and colourloss will appear. That y u will see many newbies keeping fowlr but their fishes all colourloss and hlle appearing.