trouble with angels is that having two doesn't make a pair, and there is no 100% accurate way of sexing until they breed.
If your existing angel has been alone for a while it may just try and kill off the newcomer
The easiest way to get a sure fire pair is to buy anywhere from 6-10 and let them naturally pair off on their own. I have found this to be the best way to pair up fish, especially with cichlids. I hoped this helped a little
Yah kinda but the fish stores around here dont really except fish back except for one big one but i dont really like goin there, not best care or quality, my only 3 fish deaths have been from then a blue ram, bolivian ram, and raphiel catfish.