Polyclad removal from zoa rock

[Claus84]

Hey all, I've trapped a few polyclads in my reef over the last 6 months and think I have identified a rock in which I have at least one more but its at too awkward an angle to get the trap close. Handily though it is a rock I can remove with only minor restructuring required BUT it has a fairly large zoa/paly colony on it so I'm wary about exposing it to air for too long, flushing with soda water etc.

I was thinking I might fill a salt tub with tankwater, add heater and pump and do a heavy prazipro dose, anyone tried this for flusing polyclads before?? If so how long should I leave it in there for?

thanks

Nick