Boraras rasboras

The phoenix rasbora comes from the same Borneo swamps as the chili, at the same 0.8 inches (2 cm). Its dark marks break into a blotch and a few dashes instead of a stripe. The red sits packed around those marks on a paler body. It lists 11 gallons (40 liters) at 72–81°F (22–27°C) and a pH from 5 to 7, marked medium. The strawberry rasbora is the Thai fish sold under the chili name, deeper in the body with one large dark blotch on the flank. Its red stops short of the head, and the males carry a bigger blotch than the females. It lists 11 gallons (40 liters) at 73–81°F (23–27°C), marked medium, and most of the stock is tank bred. The exclamation-point rasbora turns up mixed into chili shipments at 0.6 inches (1.6 cm). It has a long thin stripe and a round spot on the tail base. It is the only one of the six marked easy, and it takes a pH from 6 to 7.

The three from Borneo and Malaysia, the chili, phoenix and dwarf rasboras, are slim and drawn out. The strawberry, exclamation-point and micro rasboras from Thailand and Indochina are shorter and deeper in the body. Look at the dark mark on the flank next. A stripe means a chili or an exclamation-point rasbora, and a blotch means a phoenix, a strawberry or a dwarf rasbora. A round spot on the tail base marks the exclamation-point rasbora. Red that runs into the head separates the dwarf from the strawberry. The dwarf rasbora is the largest at 1 inch (2.5 cm). The chili, phoenix and strawberry rasboras stop at 0.8 inches (2 cm). The exclamation-point and micro rasboras stay near 0.6 inches (1.5 to 1.6 cm).

1. 01

   The chili's stripe

   A dark stripe on an evenly red body, no separate spot at the tail base

2. 02

   The phoenix's blotches

   A blotch and dashes instead of a stripe, red packed around the marks

3. 03

   The strawberry's blotch

   One large blotch on a deeper body, and the red stops before the head

4. 04

   The dwarf's spots

   A big blotch plus smaller spots toward the tail, the largest at 1 inch

5. 05

   The exclamation point

   A long thin stripe and a round spot on the tail base, 0.6 inches

6. 06

   The micro's pale body

   Pale with small dark spots and no red, the smallest and rarely sold

Every profile here lists a pH between 5 and 7, so hard tap water is out. Soft water over leaf litter, a dark substrate and low light bring the red out and keep the fish calm. Every one of the six is a shoaler that hides and fades when short-handed, so buy eight to ten or more. They list 7 to 11 gallons (25 to 40 liters) and 72–82°F (22–28°C) across the group. The mouths are tiny, so they need crushed flake, micro pellets, baby brine shrimp and microworms. They are safe with dwarf shrimp and too small for anything that could eat them. Keep them alone or with other nano fish.

1. 01

   Soft and acidic

   Every profile lists a pH between 5 and 7

2. 02

   Eight to ten or more

   A short-handed group hides and loses its color

3. 03

   Tiny food

   Crushed flake, micro pellets, baby brine shrimp, microworms

4. 04

   Nano tank mates only

   Shrimp-safe, and too small for anything that could eat them

The dwarf rasbora is the largest Boraras at 1 inch (2.5 cm), marked medium for 7 gallons (25 liters). It comes from Malaysia, Thailand and Sumatra, with a big blotch on the flank and red that runs into the head. Shops also sell it as the pygmy spotted rasbora, and the name dwarf rasbora gets used for the chili too. The micro rasbora is the smallest at 0.6 inches (1.5 cm) for 8 gallons (30 liters). It is pale yellow with small dark spots and no red. It lists 72–79°F (22–26°C) and a pH from 5 to 6.5, marked medium. It comes from marshes in northeastern Thailand and rarely reaches a shop.