28 gallon with a large angel fish

[86vwgti8v]

I have a large marble angel fish in my 55 gallon tank, I was wondering would it be wrong to put him in a 28 gallon. He is rather old and a 55 gallon tank is probably the smallest he been in for a long time. I was going to put just him and another small angle in it. and there is 2 catfish in it.
I'm just not sure if I feel OK with putting the big fish in that.
the big marble one
http://i7.photobucket.com/albums/y253/86vwgti8v/DSCN0554.jpg
http://i7.photobucket.com/albums/y253/86vwgti8v/DSCN1332.jpg
and the small black one.
the other 4 fish in the tank are mated pairs. these 2 fish get picked on a little.
so I want to give them their own tank. let the mated pairs do there thing in the 55.

[Lady Hobbs]

Try it and see how it goes. My angel and several rasboras are in a 30 gallon. One thing about angels, they stick pretty close to their own territories. He may feel a little crowded with the other angel there, as well, but not being picked on may be even better for him even tho it's smaller.