Excerpted From:  So you think livebearers are boring? There’s more to livebearers than guppies. Neale Monks looks at some of the interesting and unusual livebearers available to aquarists by Neale Monks The Hemirhamphridae  While at least half a dozen species of halfbeak are commonly traded, retailers simply divide them up into Celebes halfbeaks for the various species of Nomorhamphus, and silver (or wrestling) halfbeaks, which cover species of Dermogenys. Celebes halfbeaks are larger and more colourful, but they have a reputation for being rather delicate and short-lived fish. This is almost certainly because retailers do not correctly identify the different species sold, and not all species have the same water chemistry requirements. The most commonly traded species is Nomorhamphus liemi, the true Celebes halfbeak, which needs slightly soft and acid water to do well. By contrast, the red-fin halfbeak, Nomorhamphus ebrardtii, the next most commonly sold species, must have hard and alkaline water to do well. Distinguishing these two species is fairly easy: Nomorhamphus ebrardtii have straight beaks and red or orange fins, whereas Nomorhamphus liemi have curly beaks and red, black, and blue fins. A few other species are sometimes sold as Celebes halfbeaks, and generally these resemble Nomorhamphus liemi in terms of water chemistry requirements.  Silver halfbeaks, on the other hand, are very hardy, and though they lack the bright colours of the Celebes halfbeaks, they have more “halfbeaky” shape, with a nice long snout and a very streamlined shape. There are probably three different species of Dermogenys sold under the silver halfbeak name, and all will tolerate a broad range of water chemistry values. They will even do well in slightly brackish water.  In terms of care, these are fairly straightforward fish. Flake foods are readily taken, though for breeding purposes, conditioning the fish with frozen or live foods is essential. Bloodworms, daphnia, fruit flies, and other small invertebrates are particularly favoured. Silver halfbeaks feed almost exclusively from the surface, while Celebes halfbeaks are much more midwater fish, and will even take food from the substrate. All halfbeaks are jumpy, easily startled fish, and ensuring the tank is covered at all times is essential. Floating plants will help to settle these fish into the aquarium, as well as providing the fry with somewhere to hide. One peculiar characteristic of the halfbeaks generally is the high level of aggression they display to one another. Females are only marginally less aggressive than males, and both sexes will engage in short chases and fights. Although males do not fight to the death, the cumulative stress of being bullied by a dominant male can lead to the premature death of other males in the tank. For this reason, halfbeaks should be kept in either a big group (over a dozen) or in a smaller group with only a single male.   Halfbeaks are fairly easy to breed; about the only problem is keeping the mother happy and healthy through the gestation period. Unlike most other livebearers, miscarriages are common with halfbeaks, perhaps due to their nervous temperament. Once born though, the baby halfbeaks are tough and easy to raise, and will immediately accept newly hatched brine shrimps, small daphnia, frozen lobster eggs, and finely ground flake food.