help catching a fish in a Nano!

[iansfishy]

so my wife trying to be real nice buys a arabian bluelined dottyback and puts it in my Nano. Better then in the big tank i guess, but nonetheless it is evil and i want it out. I have alot of rock work and corals so taking everything out is the last thing i want to do. anyone have any ideas on how to catch this guy? hes quick and there are alot of places to hide so is thre any diy fish traps anyone knows of? Thanks