Angel fish are a unique type of fish to have in your aquarium. They are very picky and aggressive in their habitat. Although very attractive, Angel fish are not really suitable for inexperienced fish keepers. They take time to get used to and require a certain amount of attention in order to be happy. They are the cats of the aquarium. They can be difficult to maintain in any saltwater aquarium. Angel fish are easily upset by changes in water conditions. If there is any change that they are not happy with, they will surely show any dissatisfaction with aquarium life by going on hunger strike.
Angel fish are generally territorial and may be intolerant of their own kind, although different species of angel fish can generally get along. Angel fish are most tolerant of dissimilarly-sized fishes, smaller or larger, and do not pose a threat to them. However, when faced with a fish of the same proportions, quarrelling may occur. In a large aquarium with plenty of retreats, you can expect better results. Angel fish, while they seem like picky and difficult fish to maintain and take care of, they are beautiful fish and will add a lot of personality to your aquarium.