Interesting angelfish behavior

[FallenRedeemer]

So I have 2 angelfish about 5 years old. Until the week before thanksgiving they have been in the same tank. Then I found one on death's door and I rehabilitated him in a breeder box hanging on my other tank. Today he has finally recovered enough to be released into the main tank. He is not in the same tank as the other one just to make sure he didn't get picked on when reintroduced. The tanks are in a corner and the angels are both looking at eachother and swimming up and down the side of the tank nearest to eachother. I'm curious as to wether this is an aggression behavior or if they could recognize eachother after a month apart and potentially miss being together.

 

[hennaartist]

When you have a few hours that you can watch the tank fairly closely, then I would put them back in the tank together. If you notice aggressive behavior, then separate them.