Forktail Blue-Eye Rainbowfish Care Guide: Keeping Pseudomugil furcatus

If you've ever wanted a fish that flickers like a tiny piece of stained glass darting through a planted tank, the Forktail Blue-Eye Rainbowfish is hard to beat. Also called the Furcata Rainbowfish (Pseudomugil furcatus), this little gem brings constant motion, sunshine-yellow fins, and those signature electric-blue eyes to nano and community aquariums. Here at Tropical Treasures in Cheyenne, we love pointing folks toward blue-eyes when they want big personality in a small package.

The Forktail Blue-Eye at a glance 📋

The Forktail Blue-Eye (Pseudomugil furcatus) is a small schooling fish from the freshwater streams of Papua New Guinea. Adults reach roughly 2.25 inches (about 5–6 cm), with males showing the boldest yellow-and-black finnage and the dramatic forked tail that gives the species its common name. Expect a lifespan of around 2 to 3 years with good care. They're peaceful, active, and most at home in a well-planted tank with a group of their own kind. If you're browsing our rainbowfish for sale or nano fish collections, this is one of the most rewarding small schoolers we carry.

Tank size and setup 🪴

Because they're small but very active swimmers, a group of Forktail Blue-Eyes does best in a tank of at least 15 to 20 gallons, which gives them room to display and chase without stress. A longer footprint matters more than height. Aim for plenty of live plants, some open swimming lanes in the middle and upper levels, and a gentle current. A lid is essential, as blue-eyes are accomplished jumpers. Pairing them with easy beginner plants and a few floating species helps diffuse the light and brings out their best color.

Water parameters and temperature 🌡️

Forktail Blue-Eyes appreciate clean, stable water on the slightly harder, neutral-to-alkaline side. Target a temperature of 72–79°F, a pH around 7.0–8.0, and moderate hardness. They tolerate a range, but consistency is what keeps their color vivid and their immune systems strong. Weekly water changes and a lightly stocked tank go a long way. These are not fish for a brand-new, uncycled aquarium, so let your filter mature first.

Diet and feeding 🍤

In the wild these fish graze on tiny invertebrates and zooplankton, so their mouths are small and pointed upward. Offer finely crushed flakes, micro-pellets, and plenty of small live or frozen foods like baby brine shrimp, daphnia, and cyclops. Variety brings out the yellow and blue pigments beautifully. Feed small amounts a couple of times a day rather than one large meal, since they're grazers by nature.

Temperament and tank mates 🐟

Forktail Blue-Eyes are wonderfully peaceful and make excellent community citizens. They shine alongside other small, gentle species. Great companions include small rainbowfish, pencilfish and nano schoolers, small rasboras, pygmy corydoras, and dwarf shrimp. Avoid large or boisterous fish that will outcompete them for food or nip at their long fins. If you enjoy these, you might also love our Dwarf Neon Rainbowfish or Paskai Red Neon Rainbowfish for a slightly larger splash of color.

Keeping them in a group 🌊

This is the single most important tip: never keep Forktail Blue-Eyes alone or in pairs. They are social fish that need a group of at least 6 to 8 to feel secure, and males will display their fins and colors most intensely when there's a little friendly competition. In a proper group you'll see them flaring, sparring harmlessly, and constantly flickering through the plants. A solo blue-eye is a stressed, washed-out, short-lived blue-eye.

Breeding the Forktail Blue-Eye 🥚

Blue-eyes are continuous egg-scatterers that love to deposit eggs in fine-leaved plants, spawning mops, or java moss. A well-fed group in a planted tank will often spawn on its own, dropping a few eggs each day. The eggs hatch in roughly 10 to 18 days depending on temperature, and the tiny fry need infusoria or very fine foods at first. If you want to raise a good number, move eggs or mops to a separate grow-out tank away from hungry adults.

Other blue-eyes and rainbowfish to explore ✨

If the Forktail wins you over, the whole Pseudomugil family is worth a look. The Gertrude's Blue-Eye, Red Neon Blue-Eye, and Pacific Blue-Eye each bring their own twist on the blue-eyed charm. For larger rainbowfish, our Turquoise Rainbowfish and care guides for Parkinson's Rainbowfish and the Lake Kutubu Rainbowfish are great next reads. New to the group entirely? Start with our best rainbowfish for beginners guide.

Is the Forktail Blue-Eye right for you? 🤔

This fish is a fantastic choice if you have a stable, established planted tank, enjoy watching active little schoolers, and can commit to a proper group of six or more. They're a bit more demanding than a hardy beginner fish because they want mature water and small, frequent feedings, but they reward that care with nonstop color and motion. If you're brand new to the hobby, you might start with a hardier schooler first and graduate to blue-eyes once your tank is dialed in.

The bottom line

The Forktail Blue-Eye Rainbowfish packs an astonishing amount of personality and shimmer into a two-inch body. Give them a planted tank, clean stable water, a good-sized group, and varied small foods, and they'll turn your aquarium into a living jewel box. At the moment our Forktail/Furcata Rainbowfish is between shipments and out of stock, but blue-eyes move quickly, so keep an eye on our new arrivals arriving weekly or ask us to put you on the list for the next batch.

Stop by Tropical Treasures in Cheyenne to see our rotating selection of rainbowfish and blue-eyes in person, or give us a call at 307-369-1118 and we'll help you pick the perfect group for your tank. We're at 190 S College Drive, Suite D, Cheyenne, WY 82007. 🐠