Barbs: tropical Cyprinids of Asia

Barbs.  The Cyprinids (named after Cyprinus, the European Carp) are an enormously successful family of strictly freshwater fish, with over 340 genera and some 2000 species, found on every continent except South America, Australia and Antarctica. It's convenient to think of the Cyprinids in groups: besides the ''Puntius''-type Barbs in this folder, the Danios and Rasboras on the following page are also Cyprinids.  Lumped together in the constantly expanding species-group refered to as Puntius are about 120 species, of which currently there are some 78 recognized species in India and Sri Lanka alone.
 
The relationships of groups of families within two huge Cyprinid subfamilies (Cyprininae and Leuciscinae) , and closer analysis of "Puntius", are being discussed by ichthyologists, now using conservative mitochondrial ribosomal RNA and cytochrome b sequences, to supplement the traditional comparisons of skeletal details and the outward morphological similarities, which are so conservative in the Puntius group that their diagnostic usefulness in distinguishing species is limited. In June 2012 Rohan Pethiyagoda and co-workers, in a synoptic study of South Asian (Indian and Sri Lankan) ''Puntius" species, in the familiar broad sense, found five separate lineages, within which they identified three separate new species: our familiar Puntius nigrofasciatus, as type species of the new genus Pethia, becomes Pethia nigrofasciata.
 
The Barbs are an Asian clan that made their way into Europe while the Ural Mountains were being raised in Oligocene times. Some of the oldest Cyprinid fossils date to Oligocene strata in Central Europe. The Barbs colonized Africa, India and Sri Lanka. In Indonesia Barbs can be found as far east as Borneo, but no farther.
 
The Barbs are omnivores, with a need for greens. If you don't give Barbs some green feed, like spirulina flakes or, even better, blanched spinach leaves, they'll be reduced to munching on the decor. Just give them zucchini slices and they'll leave the Hygrophila alone. Barbs devour duckweed even faster than it grows.
 
Breeding links. A good basic description of setting up to breed barbs is laid out by Albert Thiel, "Breeding Barbs".  The Center for Tropical and Subtropical Aquaculture (CTSA) at the University of Hawaii, cooperating with the U.S. Department of Agriculture, posts an e-manual for commercial production of the Tiger Barb, packed with information on commercial breeding of Tiger Barbs, in order to encourage the nascent aquarium fish farming industry in Hawaii. For example, I've seen here that using a stiff spawning brush reduces the number of eggs that get eaten! And there's some material on the regrettable intentional hybridization of barbs in the trade too.
 
Breeding to maximize the number of fry. Give them a 10-gal. tank. If you can set it in an east-facing window where early sunlight will strike it, all the better. Reassure the rest of your family that this is quite temporary. Set up your tank with some aged gravel. Cut a rectangle of plastic netting with about half-inch mesh to fit the bottom of the tank, and support it with lengths of plastic tubing or whatever, so that it sits about an inch off the gravel. Add some floating stem plants like Elodea or Ambulia or some chunks of floating corkbark with streamers of Java Moss. Use a very well-cycled sponge filter from an established planted tank that hasn't had any disease in it. Fill the tank with water from the barb's home aquarium mixed about half-and-half with de-chlorinated water. The aquarium should be "instantly" cycled. To make sure, add a few drops of ammonia til it just registers on your test kit. Test again in 24 hours for ammonia and nitrite. If both ammonia and nitrite are undetectable, you're ready to go. If not, you have to wait until the cycle is complete.
 
Put the fullest, most robust female into the tank. Let her settle a couple of days and feed her lightly on live foods (you don't want flakes drifting down among the gravel). Now add the liveliest male with the reddest snout. Raise the temperature two degrees every day, til the temperature stands at 80ºF. Keep a watch on your pair: they lead up to the act with increased chasing, which the female initiates almost as much as the male. They nip at each other's anal fins and they can find themselves nose-to-tail, chasing each other til they're spinning down towards the gravel. They may just spawn without any more encouragement. If they haven't, do this: in the evening, just before "lights out," do a 50% water change with cooler water, dropping the tank temperature quite quickly as low as 74º. Cover the tank with a towel. In the morning, remove the towel, and they'll spawn in the sunlight, probably within a couple of hours. (If they don't spawn that day, start raising the temperature again and repeat the process.) Pale sticky eggs, no bigger than a dot, will fly everywhere. The spawners will eat many of them, especially as they finish spawning. Net the pair out. The eggs are invisible down among the gravel. The eggs will hatch in about two days. Before they hatch, do another 50% water change, to remove the milt that would otherwise start to be broken down by fungi and bacteria. This would be the time to color the water with methylene blue, to forestall fungus, but you have to change it out, for the newly-hatched fry are sensitive to it.
 
Breeding the natural way. Here's how I'd set up to spawn easy barbs, such as Tiger Barbs, the simplest, most natural way.  Use the plant nursery. In a half-filled 10-gallon tank in a window that gets two hours of sunlight at mid-day for half the year, I keep young plants. There are always loose tangles of Java Moss, small rosettes of Water Sprite, Anubias cuttings strapped to small chunks of roots, and currently a small Echinodorus x 'Rubin' in a clay pot.  A sponge filter run with an air pump keeps a gentle circulation. Some leaves are left to decay, and there is plentiful infusoria and biofilm. I can see copepods with my magnifying loupe, and I figure the rotifers are plentiful.  The benthic fauna that has colonised the sponge filter, some spilled compost and grit and the tank's walls, and more protozoans along the strands of Java Moss, all provide food for the newly free-swimming fry. As I write this I have tiny Cherry Barb fry, being given supplementary  eye-droppers-ful of egg yolk mixture daily. 
 
Once the fry are free-swimming, I'll start to feed them on vinegar eels and microworm for a few days, til they're all taking newly-hatched brine shrimp. Once they've grown enough to net out and put in their own grow-out planted tank, this will be ready for another spawning, of any fish that seem ready.