Angelfish are superlative animals, and with over 40 species from which to choose in the family Pomacanthidae (excluding the genus Centropyge), it is relatively easy to find an angelfish for any marine set-up. One of the most attractive aspects of keeping an angelfish in a home aquarium (beside their beauty and renowned longevity) is the fact that angelfish are highly intelligent and possess the capacity for demonstrating learned behavior. To maximize their capacity for demonstrating the range of behavior for which they are known, however, it is essential to provide angelfish with a suitable captive environment. This article discusses some factors to consider in assessing whether or not a given set-up is, in fact, angelfish-ready.
First and foremost, an angelfish-ready tank is a well-established tank, preferably aquascaped with live rock. Many experienced aquarists would never add an angelfish to a tank less than six months old. The primary reason is that angelfish are extremely sensitive to high levels of nitrates and ammonia that may be present in a tank that has not fully cycled. In addition, angelfish are happiest when provided the opportunity to graze, and it takes time to develop the beneficial algae necessary for the fish to pursue this behavioral instinct. Further, the nutritional supplement provided by algae grazing contributes significantly to the fish’s overall health.
It is also important to make sure that, in addition to being well-established, the tank provides the appropriate habitat for an angelfish. Angelfish appreciate both swimming room and caves and crevices in which to retreat, and as a general rule of thumb, each angelfish in the system should have a choice of caves (at least two) to call home.
The need for a well-established tank does not mean the hobbyist interested in keeping angelfish needs to live with an empty tank for half a year. Due to angelfish’s penchant for “ruling the roost” in all but the largest systems, they should be placed near the end of any stocking plan. By waiting to add an angelfish, the conscientious hobbyist will not only be providing for the fish’s environmental needs, but he or she will also be avoiding undue aggression, as the angelfish’s tankmates will already have had the opportunity to establish themselves and their territories.
Finally, an angelfish-ready tank also needs the appropriate equipment to meet the needs of these higher than average waste producing fish. Additional mechanical filtration is often warranted when keeping angelfish, as is above average water flow to ensure excellent oxygen exchange. Once again, providing these environmental conditions in the tank will not only benefit the fish’s biological needs, but it also contributes to the behavioral health of the fish. For example, most angelfish are attracted to stronger currents in the tank and will indeed “play” in these currents. Such behavior is interesting to watch and is also reported to limit aggression.
Once the tank is deemed angelfish-ready, the aquarist can obtain his or her individual specimen(s). While the selection of an appropriate angelfish species is beyond the scope of this article, a few general comments about selection are appropriate here. Most important, for the aquarist interested in observing an angelfish’s capacity for learned behavior, it is recommended that he or she acquire a relatively young fish. Juvenile angelfish are less aggressive and easier to transition to a captive diet, and they have yet to establish their behavioral patterns and habits. Perhaps nothing in the hobby is as rewarding as watching a juvenile angel grow and develop its “personality” based on the aquarium set-up and the aquarist’s husbandry practices.
