I'm running bio balls on my 180g
I've heard that they are ok for a FOWLR
tank but not reef or mixed tanks
Use a good protein skimmer when using bio balls
They are a nitrate factory I've heard, there is to much space for nitrates to get trapped.
Alternatives would be a sump with live rock or a refugium. I'm not sure about using live rock ruble in place of bio balls since it doesn't stay submerged.
For now I'm sticking with bio balls until it doesn't work for me
Interested in hearing everyone else's opinion