The Harlequin Rasbora (Trigonostigma heteromorpha) makes an absolutely captivating addition to any aquarium. Its body is mostly a bright pinkish color, but it is known for the black or dark purple mark on its sides. The combination of these bold colors really makes this fish stand out from all others, especially when paired with dark-colored substrate. Males tend to be more colorful than females, and its "lambchop" markings are usually more pointed in appearance. Females are often rounder in shape. Its diminutive size makes this fish great for nano tanks!
The Harlequin Rasbora is easy in care as long as it has stable water parameters with good water quality. Like all rasboras and danios, this fish is completely peaceful and totally safe to keep with other fish (as long as the other fish are peaceful as well), snails, shrimp, and live plants. While it is safe with adult shrimp, it might prey on shrimp fry. The Harlequin Rasbora is a schooling fish that can only thrive in groups of at least 6-8 specimens. Keeping this fish in a large school will ensure its most natural behavior, especially top coloration from males as they compete for the attention of females. When this fish is healthy and placed in a well-cycled and densely planted aquarium, it is fairly likely that it will spawn, and you may see fry start to appear.
The Harlequin Rasbora is omnivorous and not too picky about eating. It will likely eat fish flakes or pellets, but also needs a varied diet of frozen meaty and/or live meaty foods (such as brine shrimp, bloodworms, daphnia, and insect larvae) in order to breed or even show its best coloration. It will also eat blanched vegetables such as lettuce, zucchini, kale, etc. The Harlequin Rasbora is a very undemanding, classic fish that is a prime candidate for the planted or nano aquarium!
What We Like About This Fish:
- Unique pattern and striking colors
- Ideal schooling fish
- Safe with plants
- Completely peaceful
RECOMMENDED TANK PARAMETERS:
- Temperature: 72° - 79° F (22° - 26° C)
- pH: 6.0 - 7.0
- KH: 2 - 10 dKH
- Minimum tank size: 10 gallons
- Diet: Omnivorous. Will readily accept most flake foods and algae wafers, as well as freeze-dried daphnia, bloodworms, tubifex, and brine shrimp.
- Social behavior: Peaceful, schooling/shoaling.
- Origin: Tank-bred, but indigenous to Thailand, Malaysia, Singapore, Borneo, Sumatra
- Average adult size: 1.4 - 1.8 inches (3.5 - 4.5 cm)