Rasboras, danios & minnows · Rasbora trilineata

Scissortail rasbora care guide

Also called: Three-lined rasbora, Scissor-tail rasbora, Scissortail, Three-line rasbora

The scissortail rasbora is a fast, silvery schooling fish named for its black-and-white tail that flicks like scissors. It's peaceful but grows to nearly 5 in (12 cm), so it needs a tank 4 ft (120 cm) long and a tight lid.

Scissortail rasboras need a tank of at least 55 gallons (208 L), a group of 6 or more, and water at 22–25°C (72–77°F) with a pH of 6–7.5. They grow to about 12 cm (4.7 in) and are peaceful.

Plan a tank with scissortail rasborasSee all tank mates

Scissortail rasbora quick facts

Scientific nameRasbora trilineata
FamilyDanionidae
OriginMekong and Chao Phraya basins, Malay Peninsula, Sumatra and Borneo (most sold today are farm-bred)
Adult size12 cm (4.7 in)
Minimum tank55 gallons (208 L), at least 120 cm (47 in) long
Temperature22–25°C (72–77°F)
pH6–7.5
Hardness (GH)4–12 dGH
Group size6 or more (schooling fish)
TemperamentPeaceful
Swims atTop
DietInsectivore
Care levelModerate
Lifespan5–7 years
Safe with shrimp?No, eats shrimp
Safe with plants?Yes
  • Known jumper: keep a tight-fitting lid.

Tank setup

A group of 6 or more needs a tank at least 4 ft (120 cm) long, such as a 55-gallon (208 L). Keep the middle and top open for swimming, with plants and wood around the edges. A tight-fitting lid is essential because they jump. Good filtration with moderate flow suits these active fish.

How many scissortail rasboras in a tank?

The smallest common tank that suits scissortail rasboras is a 55 gallon. Here is roughly how many fit in each size when they are the only fish, based on adult size and waste output. Leave room if you want tank mates.

TankScissortail rasboras (alone)
3 gallonToo small
5 gallonToo small
10 gallonToo small
15 gallonToo small
20 gallonToo small
20 gallon longToo small
29 gallonToo small
40 gallonToo small
55 gallon6–14
75 gallon6–19
125 gallon6–32

What you need for scissortail rasboras

Sized for a 55 gallon tank, the smallest common size that suits a group of 6 scissortail rasboras. For a different tank or a mix of fish, use the stocking calculator for a list sized to your plan.

Tank and equipment

Food and extras for scissortail rasboras

Product links go to Amazon search results. As an Amazon Associate we earn from qualifying purchases, at no extra cost to you. Disclosure.

Water parameters

Keep them at 22–25°C (72–77°F), pH 6.0–7.5 and soft to moderately hard water (about 4–12 dGH). They handle a fairly wide range of water chemistry but do poorly when waste builds up. Add them to an established tank, change water weekly and acclimate new fish slowly, over a couple of hours.

Best tank mates for scissortail rasboras

These popular species share scissortail rasboras' water needs and temperament. See the full list of 68 good matches.

Avoid keeping scissortail rasboras with

  • Cherry shrimp: Scissortail rasbora eats small shrimp like cherry shrimp.
  • Boesemani rainbowfish: They need different temperatures: Scissortail rasbora 22–25°C (72–77°F), boesemani rainbowfish 26–29°C (79–84°F).
  • Chili rasbora: Scissortail rasbora can eat chili rasboras: they're small enough to fit in its mouth once it's grown.
  • Chinese algae eater: Chinese algae eater is aggressive and will bully or injure peaceful scissortail rasboras.
  • Convict cichlid: Convict cichlid is aggressive and will bully or injure peaceful scissortail rasboras.
  • Discus: They need different temperatures: Scissortail rasbora 22–25°C (72–77°F), discus 28–30°C (82–86°F).

Feeding

In the wild they feed mainly on insects that land on or fall into the water. Use a good flake or small pellet as the staple, with frozen or live bloodworm, brine shrimp, daphnia or mosquito larvae several times a week. They are quick, greedy eaters, so make sure slower tank mates get their share.

Behavior

Scissortails are peaceful but very active, and they spend most of their time in the upper half of the tank. Keep at least 6, ideally 10 or more, or they become nervous. Good tank mates are peaceful fish of similar size, such as larger tetras, barbs, rainbowfish, danios, loaches and corydoras. Avoid nano fish and dwarf shrimp, which they can stress or eat.

Breeding

They scatter eggs, give no parental care and are one of the easier large rasboras to breed. Use a long, shallow, dim tank with mesh or matting on the bottom, slightly acidic water and a temperature at the warm end of their range. Remove the adults after a day or two because they eat eggs. Fry hatch in 1–2 days and take baby brine shrimp or microworms once free-swimming.

Tips from experienced keepers

  • Fit a tight lid and cover gaps around filters. Scissortails are strong jumpers.
  • Plan for adult size. The small fish sold in stores grow to nearly 5 in (12 cm).
  • Choose a long tank over a tall one. They need horizontal room to swim.
  • Don't mix them with chili rasboras, other tiny nano fish or dwarf shrimp. Adults may eat them.
  • Acclimate slowly. They react badly to sudden changes in water.

Frequently asked questions

How big do scissortail rasboras get?

In aquariums they usually reach about 4–5 in (10–13 cm), and wild fish can grow larger. They are often sold at 1–1.5 in (2.5–4 cm), so plan the tank for adult size.

What size tank does a scissortail rasbora need?

A school of 6 or more needs a tank at least 4 ft (120 cm) long, such as a 55-gallon (208 L). Smaller tanks don't give these fast swimmers enough room.

Are scissortail rasboras aggressive?

No. They are peaceful and don't bother fish of similar size. Their speed and appetite can stress shy or slow fish, and adults may eat very small fish and dwarf shrimp.

Sources

We checked these references when writing this page. Values are for healthy long-term keeping, not survival limits. Last reviewed 2026-10-13. See our editorial policy.