Quarantine

[Aquattro]

I use a foam block in an aquaclear HOB filter. I keep a block cycled in my main sump for when it's needed. Liverock works too, but if you have to use meds, which is always a likely maybe, are you willing to sacrifice the rock? If so, then go rock, the fish will probably like it more. The foam block though is disposable or bleachable.