In our previous episode of Reef Nuggets, we explored our options for peaceful and lesser known damselfish to add a little spark of colour and life to our aquariums. Having vanquished the hateful stereotype that not all damsels are malevolent and malicious, we’ll delve into another touchy topic today. Having butterflyfish in reef aquariums. Yay or Nay. Possible, or impossible? We’ve already touched on this topic before, and although we don’t usually repeat posts, this revised edition is longer, more comprehensive and has more examples.
Terrestrial butterflies are always a welcomed and beloved sight in gardens and wild areas. Likewise for butterflyfish. Although only related by name and nothing else, butterflyfish are iconic reef denizens that add colour and life to coral gardens in the wild. Think of a fish to represent a coral reef and there’s a high chance it could actually be one of the many butterflyfish species.
For such a high standing reef icon, you would imagine that butterflyfish would be more popular in the aquarium. Are aquarist put off by the notion that all butterflyfish are coralivorous? Or are they simply put off by the fact that butterflyfish are touchy and difficult to keep. Angelfish (Pomacanthidae) are perhaps just as colourful, just as iconic and just as notorious for their pension for being destructive toward corals, yet the family on a whole is celebrated between all its genera in the aquarium hobby. Like Angelfish, there are exceptions in this family that are indeed very suitable for the reef aquaria. Reef safe AND easy to maintain? Is this a myth?
Not quite. The family Chaetodontidae is large and diverse, with many species adapting to live and thrive in various biological niches. Although all butterflyfish are highly compressed in their body configuration and are adapted to living in the reef, they have adapted amongst themselves, different feeding styles. There are three main feeding categories we can class butterflyfish in. They are,
– Benthic opportunistic,
The majority of butterflyfish fall within this category. Many species in the main genus Chaetodon are benthic opportunistic, and feed on a variety of invertebrates that live within the reef structure. Polychaete worms, small crustacean, filamentous algae, fish eggs, tunicates, sponges and even coral are part and parcel of a butterflyfish’s diet. There are some notable exceptions in this category which do not, or rather hardly consume coral. These are members of the genus Chelmon and Forcipiger. With intelligent coral selection and caution, members of the genus Prognathodes, Roa, Coradion and the subgenus Roaps can also be housed in a reef aquarium with moderate success. We will touch more on this later.
– Coralivorous (Facultative/obligate)
Certain butterflyfish are highly adapted and experts at their craft of coral eating, and these especially apply to obligate coralivorous butterflyfish. Needless to say, these are not advisable to maintain in the home aquarium because of their strict diet. The obligate SPS eating butterflies are well known, and includes Chaetodon ornatissimus and its complex, C. austriacus and its complex, C. triangulum and its complex as well as a handful of other species.
Facultative coralivores are species that take coral as a food source, but can live without it and are able to obtain energy from other means. These include C. quadrimaculatus who although not dependant, has a pension for Pocillopora, and C. ocellicaudus who is a soft coral specialist and is able to eat noxious species like Sarcophyton, Sinularia and Lemnalia. Needly to say, this entire group of butterflies are not suitable for a standard reef aquarium unless housed in a huge set up with a sustainable source of coral to spare.
– Pelagic planktivorous
This is the best group of butterflyfish for the reef aquarium, and is the Genicanthus equivalent of the butterflyfish family. The genus Hemitaurichthys is perhaps the only genus in this family that is almost strictly planktivorous. Although they do scour the reef for the occasional morsel, they primarily feed by picking off floating particles and zooplankton in the water column. Like the Genicanthus angels, Hemitaurichthys have small mouths and are often seen schooling high above the reef picking food as it floats their way.
Now that we know roughly the three basic feeding groups, we can use this information to our advantage and choose the species best suited for the home aquarium. Needless to say, all members of the facultative and obligate coral eating groups are off the table. Unless you own a public aquarium with fields of corals growing faster than your butterflyfish can eat, it is not advisable. This leaves us with the benthic feeders and the planktonic feeders. Let’s meet the species.
Chelmon is a small genus of beaked butterflies that are most often found in shallow silty reefs. They can be found in tide pools, estuaries and boat harbours. The prominent and conspicuous beak is an adaptation for picking at sessile invertebrates living amongst rock or mud, and they are specialist worm hunters. Therefore all feather worms and polychaetes are on the menu. Small anemones such as Aiptasia are also often taken. Their mouthparts are too small and delicate and are not built for coral eating, so Chelmon is on a whole, very safe. There is definitely a higher chance that a Centropyge dwarf angel will nip at your coral instead of a Chelmon butterflyfish. There are three species in this genus, and they are C. rostratus, C. marginalis and C. muelleri.
Unfortunately, these are often difficult to get feeding initially, and a lot of patience and live food may be required initially to get a feeding response. It is however, a worthy candidate for a reef and is definitely one of the safer choices.
Forcipiger is another genus of beaked butterflies, but unlike Chelmon, they have longer more delicate beaks and tinier mouths. There are three members in this genus, with F. wanai being the newest addition in 2012. All Forcipiger members are yellow overall with a black mask, and they are differentiated based on beak length, meristics, and colour (in the case of F. wanai being brownish on the body). Like Chelmon, their beak length and tiny mouths are not suited for coral eating, but rather at picking off sessile invertebrates and worms. In addition, F. flavissimus is an easy species to keep, and readily accepts frozen food such as mysid and brine shrimps, as well as finely chopped seafood. With a little bit of training, they will accept small flake and pelleted foods as well. If your reef is lacking colour and you’re thinking of trying a butterflyfish, there is no reason why this handsome species would not make a good candidate.
Roaps, Prognathodes and Roa
Roaps is a subgenus of Chaetodon, and Prognathodes is a genus of Atlantic butterflies and both share a common love for deeper waters. Fond of even deeper waters still is the genus Roa, where majority of the species inhabit the mesophotic twilight zone. Although none of these butterflies can be classified as specialist invertebrate only feeders like Chelmon and Forcipiger, they fall into the safer end of the benthic opportunistic spectrum, and with careful selection of coral choices, may prove to be relatively okay choices for a reef aquarium.
There are five members in Roaps, and they are C. tinkeri, C. flavocoronatus, C. declivis, C. burgessi and the only Indian Ocean representative, C. mitratus. The black and white species hybridise where their range overlaps in the Pacific, and various intermediates have been found in Tarawa as well as the Marshall Islands. Personally, I have kept C. tinkeri, C. mitratus as well as C. declivis in a mixed reef with very few issues.
Firstly, this is a hardy genus that is extremely easy to feed and will readily accept pellets and flake food within the first few days of acclimation. They are not shallow water reef dwelling species in the wild, so their primary diet does not consist of corals. Their behaviour in aquarium is very similar to dwarf angels. They are curious and will nip on various surfaces such as live rock, sponges and occasionally your coral. Based on the specimens that I have kept, I personally never had any issues with them actually eating the coral, and the occasional nip on an SPS or two was observed to do no harm. I would say their safeness is similar to that of a Centropyge, and if you’re willing to risk a dwarf angel in a reef, then by all means, add a Roaps if you want to. Keep them well fed throughout the day and there should not be any issues, and if need be, their greedy nature would mean easy trapping.
The same can be applied to the Atlantic genus Prognathodes and the genus Roa. All the Prognathodes with the exception of P. aculeatus are normally found in deeper waters where coral growth is not as dense as the shallows. They are also relatively easy to feed as compared to many Chaetodon, and are very popular with Japanese SPS enthusiast. Roa is extremely deepwater and like Prognathodes and Roaps, probably sees less coral in their lifetime. They are very expensive and rare, so it is unlikely that a Roa would end up in a brightly lit reef tank anyway.
In the video above, this manicured SPS Japanese tank features P. marcellae as well as P. declivis, along with a plethora of other angelfish species. Remember earlier in this article when we mentioned careful selection of coral choices? SPS is one of them. Many butterflies are curious and like to nip on things, but when it comes to SPS corals, few are able to actually extract the polyps. That is why coralivorous butterflyfish are so adept at what they do, while the rest are not. With that in mind, a full blown SPS reef is the best bet for a butterflyfish, contrary to what many people think. With the right species of course. Conversely, a full blown SPS reef is not the best bet for a butterflyfish, if your selection happens to be C. ornatissimus.
If your tank is largely soft coral dominated, then by all means, go ahead and add in a Roaps or a Prognathodes. A soft coral only tank expands your choices to include an even larger assortment of butterflies, and species in the “miliaris complex”, “sedentarius complex” and even “xanthurus complex” would be ok. As we’ve mentioned before, coral selection and butterflyfish selection go hand in hand. Many soft corals are very noxious, to deter would be predators. Many reef fishes likewise, even butterflyfish, would leave them alone. However if your butterflyfish in mind happens to be C. melannotus or C. ocellicaudalis, then do not add them in a soft coral tank. These two sibling species are suited for munching on toxic softies.
Fine ok, if you’re not a risk taker, and you don’t like the odds, and you’re really iffy about butterflies but still would like to try them out, then take off your safety harness and go for Hemitaurichthys. There are four species in this genus, two of which are very commonly offered in the hobby. H. polylepis, the yellow pyramids, and H. zoster, the black pyramids. As mentioned above, Hemitaurichthys are planktivorous and probably will not take a second look at your corals. There’s a higher chance of a wayward surgeonfish nipping at your corals than a pyramid butterflyfish would.
Take a look at Bradley’s reef. This is a prime example of a healthy, diverse reef with mixed coral and butterflyfish and angelfish. Bradley’s reef is home to some species that are even less safe than any of the ones we recommended here! Heniochus diphreutes and Chaetodon kleini can be seen in the picture, and at the corner, a large Apolemichthys xanthopunctatus (Goldflake Angelfish) can be seen as well. With all these supposedly evil coral eating fish around, it shouldn’t be possible for those corals to be fluffing up and growing right? Well, with the correct selection of fish, there is no reason why you should leave butterflies out of your list the next time you plan to stock a reef tank. Myth, debunked.