Appearances of fishes can indeed be deceiving. To take one look at the longnose butterflyfishes, you'd expect them to be in the same hardiness category as the pinnatus batfish. Such is definitely not the case. If you are careful to select an individual that has not been beaten up physically and/or emotionally through collection and transport, these yellow beauties do exceptionally well in marine systems.
Forcipiger flavissimus (Jordan & McGregor 1898), also known as Yellow Longnose Butterflyfish, Forcepsfish. Wide variety of foods taken, rarely corals. Widest distribution of B/Fs, from east coast of Africa to west coast of Central America. To eight inches overall length.
Natural and Introduced Range F. flavissimus is found in most of the Pacific, Indo-Pacific and Red Sea; F. longirostris overlaps the shorter nose sympatriate over much of its range.
Size: Most offered are four to six inches in overall length, tail to rostrum. A truly gargantuan specimen will be about ten inches.
Favored parameters are a pH of 8.0 to 8.4, temperatures in the high seventies, low eighties, and an artificially low specific gravity of 1.020. The latter to allow higher gas diffusion, concentration, and aid in reducing parasite loads. Keep the pH high and make frequent partial water changes.
Biology/Other It should be mentioned that these fishes display some unusual behavior. Don't be unduly surprised should you catch yours swimming or hanging upside down; or that it might "spit" water in your direction at the surface. Also, let me mention their blanched whitish appearance on being exposed to light from dark conditions; like sleep or removal from a shipping box. A loss of yellow during the day is a fast sign that you need to be looking for a cause; probably fright from bullying, or diminished water quality.
One last color note (I promise); check out the disruptive black bar over the fish's eyes and prominent 'eye-spot' at the tail for prospecting predators to bite at. Okay, I feel better.
Filtration Longnoses are stout fishes but do require clean, well-filtered water. Circulation cannot be too strong to suit them either; keep the water moving.
Display Giving these marine organisms open areas and rocks, coral where they can seek refuge in a hex or show type aquarium, results in better adjusted, longer lived specimens. The system should be no smaller than forty gallons, ideally with twenty or more gallons set aside per butterfly.
Territoriality Can be problematical. These fishes are best kept one to a system. The best wholesalers keep their specimens in seperate cubicles. Overcrowding is stressful, but does temporarily cut down on squabbling.
Introduction/Acclimation Simple enough. One suggestion: put your longnose in as one of the first fishes, maybe right after the damsels. They need to feel at home so as to get their share of offered foods.
Predator/Prey Relations Outside of quarreling with other longnoses, these fishes are peaceable. Be wary of placing them with larger predatory fishes however. I have seen them used as bait by island fisherfolk, and can recount more than one tearful aquarium gulp-loss.
Feeding Despite their looks, these B/F's accept all types of foods, frozen, fresh and prepared, with gusto. You'd think that their long "beaks" and priser-like teeth would be only suited for snipping out invertebrates from tiny crevices, but these fishes will try almost any size and shape of foods offered. It's best to defrost frozen items.
Please do include some meaty foods daily; bloodworms, shrimps, clams. These fishes are active, seeking food all day on the reef and in aquaria, and do well only when offered sufficient nutrition. Be wary of relying solely on one type of dry or frozen prepared food type.
Disease: Infectious, Parasitic, Nutritional, Genetic, Social These fishes tend to be very infectious- and environmental disease resistant. They are more susceptible than "average" to marine "ich" (cryptocaryoniasis); this is easily cured with copper remedies and specific gravity manipulation (lowering).
Two other all-too-often fatal complaints are so-called secondary bacterial infections most-often resultant from bad handling. The genus Vibrio is often cited as implicated, following a mouth, body "incident" due to user-failure. After a reddish area forms at the mouth, fin-ray base or body flank, there is almost no chance of recovery.
I'd really like to do my bit here for vastly reducing these losses; they result from beatings in the wild, the tank, shipping bags, and in-between. What To Do: Be Careful, don't wallop the fish; it's that simple. If/when you use a mesh-type net (some collectors use clear-bottom varieties), make sure it is one composed of soft, fine material. Longnoses have a real problem with getting their snouts and fin rays, principally the hard dorsal, anal and pelvics, snagged in coarse netting; resulting in tearing and infection. Real professional fish handlers gently cradle the fish in fine nets with their hand behind, when lifting from and to water to diminish thrashing.
Similarly, providing the right size, shape, orientation with an adequate amount of water in a shipping bag is important. Allow me to elucidate. The worst, though typical arrangement is to plop a specimen into a bag just large enough to accommodate the animal head to tail. No wonder it ends up with a broken, fungused snout, torn fins, and you with a punctured bag. What to do: grant the organism enough bag space to turn around, and either double-bag and ship in the dark, or provide a dark 'spacer' (even newspaper works) between bag layers. Wholesalers and transshippers who can scarce afford the space and weight that retailers and hobbyists can would do well to ship these fishes on their sides. Yes, I'm very serious. By placing the same (albeit too small) size bag on it's side, the butterfly will lay down, struggle far less; and therefore use less oxygen, produce less wastes, pierced bags... you know, less mortality. This is not pie-in-the-sky theory. I've done it; try it, it works.
Summary: There is a reason why these butterflies are ever-popular. They're gorgeous and they live in captivity. Don't let their frilly looks throw you. Learn what a good specimen looks like and you will be successful with these species. If ever there was a "first-timers" butterflyfish, these would be them.
With the permission of Robert (Bob) Fenner webmaster of WetWebMedia ()
Forcipiger flavissimus (Long-nosed Butterflyfish)