I had an angel in my 220, this is what I did:
1 fish traps - about three different types
2 fishing line with a hook
3 gig
4 drained tank (didn't work as he just hid behind the rocks with all the other fish)
5 got two 100 gallon rubbermaid containers from tractor supply, drained my entire tank, took out all water, rock and coral, and caught that &%*&$(*&^%. Oh and I had Kevin Garrison who took the rock out of the tank like they were feathers.
It was a nightmare. If you have a reef and no other tanks I suggest staying away from angelfish... If you have a tank to move coral to that is being nipped then it may be worth the risk.