Copper is an immunosuppressant so it's always a good idea to help the fish by adding a bit of O2. An airstone is good, but a powerhead aimed up at the surface where it is actively rippling the water's surface provides the highest O2 exchange.
Copper is an immunosuppressant so it's always a good idea to help the fish by adding a bit of O2. An airstone is good, but a powerhead aimed up at the surface where it is actively rippling the water's surface provides the highest O2 exchange.