- Species Name: Oryzias woworae
- Common Names: Daisy’s Ricefish, Daisy’s Blue Ricefish
- Size: Up to 1 inch
- Lifespan: Up to 4 years
- Native Distribution: Sulawesi, Indonesia
Ideal for nano-aquariums, the Daisy’s ricefish (Oryzias woworae) is a diminutive freshwater species that grows to a maximum length around 1 inch. Though they may be small, these fish are brightly colored and can make quite the impression when kept in groups of six or more.
Daisy’s ricefish are a schooling species but, due to their size, they’re not recommended for standard community tanks. These fish are most likely to thrive in a planted tank with similarly sized species. They’ve even been known to breed readily in the proper setup.
Anatomy and Appearance
The Daisy’s ricefish is sometimes called Daisy’s blue ricefish for the coloration exhibited by adult males of the species. The scientific name for the species’ genus, Oryzias, is a reference to the tendency of some species of this group to inhabit rice paddies. The species name and its common name is a reference to Daisy Wowor, the Indonesian carcinologist who originally collected and described the species.
Like other ricefish, the Daisy’s ricefish is a small ray-finned species. They’re easily distinguished by their unique jaw structure and for having an extra bone in their tail. Male Daisy’s rice fish develop a shimmering light blue coloration while females are yellow-gold in color. Adult males often exhibit bright red edging on their fins, and sometimes the same color appears in the belly area. Females may show hints of orange along the underside of the back half of the body.
This contrasting coloration makes it easy to differentiate between males and females, though males also tend to be slimmer than females with longer dorsal and anal fins. If you plan to breed Daisy’s ricefish, you’re likely to end up with a mixture of the two sexes if you start with a large enough school.
Ideal Aquarium Setup
In the wild, Daisy’s ricefish are endemic to a single stream in the Southeast Sulawesi province of Indonesia. This stream, Mata air Fotuno, is located on the island of Muna. It’s a slow-moving freshwater stream with plenty of aquatic plants and leaf litter. When kept in captivity, Daisy’s ricefish are most likely to thrive in a tank setup that mimics their natural habitat.
Though Daisy’s ricefish only achieve a maximum length of around 1 inch, they need a tank large enough to accommodate schools of six or more. Not only will this species feel more comfortable in a big group, but it’s the best way to showcase their unique coloration.
A minimum tank size of 10 gallons is recommended, though extra space is always welcome. If you plan to keep Daisy’s ricefish as part of a community tank, consider the bio-load and space requirements of all your fish to determine the proper tank size.
Daisy’s ricefish are a somewhat delicate species, in part due to their small size. They’re best added to an established aquarium where water parameters have already stabilized. The water should be kept warm—between 73°F and 80°F—with routine water changes to maintain stable chemistry. These fish can tolerate slightly acidic to neutral pH in the 6.0 to 7.5 range. They can tolerate a wide range in water hardness from 90 to 268 TDS or 9 to 19 GH.
Though Daisy’s ricefish are fairly adaptable, they’ll really thrive in a biotope tank that mimics their native habitat. A planted aquarium is a must and sandy substrate is preferred. Be sure to decorate generously with driftwood and smooth rocks. Your fish may also appreciate a sprinkling of leaf litter.
Diet and Feeding
Daisy’s ricefish are omnivores likely to accept a wide variety of foods. The challenge is finding foods small enough to fit in their tiny mouths. These fish will thrive on a combination of omnivore flake foods, micro-pellets, and freeze-dried brine shrimp or bloodworms. Ideal frozen foods include daphnia, baby brine shrimp, and smaller bloodworms.
In the wild, this species has been observed grazing from solid surfaces, so algae may be part of their natural diet. A heavily planted tank is best for cultivating this kind of habitat and will also provide plenty of surface area on which edible biofilm will accumulate.
Temperament and Tank Mates
The Daisy’s ricefish is a peaceful species that can be quite active when kept in large enough schools. Though they’re gentle enough on their own, these fish are too small for the typical community tank. They’re best kept in a small school in a nano tank or with similar-sized species in a large community tank. If you plan to breed these fish, they should be kept alone.
These fish typically inhabit the middle to upper level of the water column, so they can easily be kept with small bottom dwellers like pygmy Corydoras or small catfish like Otocinclus. Some of the best tankmates may be freshwater dwarf shrimp. The adult shrimp will be too large for Daisy’s ricefish to eat and this species is unlikely to feed on baby shrimp if they’re on the bottom of the tank.
Breeding Daisy’s Ricefish
Daisy’s ricefish are prolific breeders and reproduce readily in well maintained aquariums. Mature females are able to produce batches of 10 to 20 eggs every few days—even on a daily basis. If you prefer to avoid breeding your fish from the start, get your first fish from Shrimpy Business and dwell into the breeding habitats once you have everything set up for them.
Unlike many small freshwater fish, Daisy’s ricefish don’t scatter their eggs. Rather, the female expels the eggs in a single mass as the male fertilizes them. The adhesive eggs will continue to hang from the female’s body until she deposits them singly or in small groups among the vegetation in the tank. Fine-leaved stem plants make ideal spawning surfaces.
Daisy’s ricefish eggs hatch after a temperature-dependent incubation period that ranges from one to three weeks. The adult fish largely leave unhatched eggs alone, though they may feed on the free-swimming fry. Some of the fry will likely survive in more densely planted tanks, though you can also remove the eggs or fry to a separate rearing container. Just be mindful of housing fry from different spawning periods together—the older may feed on the younger and smaller fry.