Scarlet Badis Care Guide (Dario dario)

The Scarlet Badis (Dario dario) is one of the tiniest, most jewel-like fish in the freshwater hobby. Males glow ruby-red with sapphire-blue bars, top out under an inch, and behave more like miniature cichlids than typical nano fish — staking out little territories among plants and stalking micro-prey. They’re stunning in a planted nano tank, but they have one quirk that catches new keepers off-guard: most refuse flake and pellet food. At Tropical Treasures Wyo in Cheyenne we hand-feed them live and frozen foods in-store, and that’s the single most important thing to plan for before you bring a group home.

Ready to add a school of living rubies to your nano tank? Shop Scarlet Badis here — and read on for the full care, feeding, and breeding rundown.

Quick Facts

  • Scientific name: Dario dario
  • Common names: Scarlet Badis, Scarlet Gem, Bengal Dario
  • Origin: Slow streams of West Bengal, India (Brahmaputra basin)
  • Adult size: 0.5–0.8 inches (males slightly larger)
  • Lifespan: 3–5 years
  • Temperament: Peaceful overall; males territorial with each other
  • Care level: Intermediate (because of feeding)
  • Minimum tank size: 10 gallons for a small group

Are Scarlet Badis Hard to Keep?

Water-wise, no — they’re hardy in stable, mature tanks with soft to moderately hard water. The challenge is feeding. Wild-type Scarlet Badis are micro-predators and many simply will not recognize dry food as food. A keeper who can offer live or frozen meaty foods several times a week will have no trouble. A keeper who only feeds flake will lose them to slow starvation. Plan the food before you plan the fish.

Tank Size & Setup

Minimum tank size: 10 gallons for 1 male and 3–4 females. A 15–20 gallon long is much better if you want multiple males, since each one will claim a small territory.

Substrate

Fine sand or small dark gravel. A dark substrate makes their red color pop dramatically.

Aquascape

Heavily planted is non-negotiable. Use a thicket of stem plants, mosses, and floating plants to break sightlines. Driftwood, leaf litter (Indian almond, oak), and small caves give males distinct territories and reduce squabbling. Dim, shaded lighting brings out their best colors.

Filtration & flow

Sponge filter or a gentle hang-on-back with a pre-filter sponge. Scarlet Badis hate strong current and are too small to fight it. The sponge also protects them and any fry from being sucked in.

Heating

Use a reliable adjustable heater set to 75–78°F. They tolerate a wider range, but stable temperature in the mid-70s is the sweet spot.

Water Parameters

Parameter Target Range
Temperature 72–79°F (22–26°C)
pH 6.5–7.5
GH 5–15 dGH
KH 3–8 dKH
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate < 20 ppm

Always add fish to a fully cycled tank and treat tap water with a dechlorinator like Seachem Prime before water changes.

Diet & Feeding

This is the single biggest topic for Scarlet Badis. They are obligate micro-predators. Plan to offer:

  • Live baby brine shrimp (their absolute favorite)
  • Live or frozen daphnia, cyclops, and grindal worms
  • Microworms and vinegar eels for fry
  • Frozen bloodworms (chopped small) for adults

Feed small amounts 1–2 times daily. Some individuals can be trained onto crushed micro-pellets after months in captivity, but never count on it. If you’re not willing to keep frozen or live food on hand, choose a different nano fish.

Tank Mates

Scarlet Badis are peaceful with non-competitive tank mates but will lose at the food bowl to anything faster. Match them with slow, gentle eaters.

Great tank mates

Avoid

  • Bettas, gouramis, angelfish, and any fish big enough to eat them
  • Fast, greedy feeders like tiger barbs, danios, and most tetras — they will outcompete badis at every feeding
  • Fin-nippers of any kind

Risky but possible

  • Ember tetras and very calm small tetras — only in larger tanks with target feeding
  • Small, peaceful guppies in a heavily planted tank, if food is delivered to the badis directly

Male vs. Female

Males are vivid scarlet with 7–8 vertical iridescent blue bars and longer, pointed fins. Females are noticeably smaller, drab tan-gray, and rounder when carrying eggs. A 1 male : 3+ female ratio keeps aggression manageable.

Breeding

Scarlet Badis breed readily in heavily planted, mature tanks — often without any intervention. Males pick a territory (usually a moss patch or cave), display intense color, and lead receptive females in for spawning. Eggs are scattered into mosses and hatch in 2–3 days; fry are tiny and need infusoria, then microworms and live baby brine shrimp. Parents generally ignore eggs but adults may eat free-swimming fry, so a dedicated breeding tank is best for high yields.

Common Problems & Diseases

  • Starvation: The #1 killer. Hollow bellies and faded color mean they’re not eating dry food — switch to live/frozen immediately.
  • Ich: Treat at the low end of medication doses; small fish are sensitive.
  • Internal parasites: More common in wild-caught individuals; quarantine new arrivals.
  • Fungal/bacterial infections: Almost always secondary to poor water quality. Keep nitrates low and do regular small water changes.

Tips for Long-Term Success

  • Set up the tank 4–6 weeks before adding badis — mature biofilm provides micro-prey snacks.
  • Keep the lid tight; they don’t jump often, but they can.
  • Quarantine new arrivals for 2–3 weeks before introducing them to a display tank.
  • Target-feed shy individuals with a long pipette so faster tank mates don’t steal every meal.
  • Limit males per tank unless you have plenty of plants and floor space.

Frequently Asked Questions

Are Scarlet Badis hardy?
Yes, in stable, mature tanks. The hard part is feeding, not water chemistry.

Will Scarlet Badis eat flake food?
Most refuse it permanently. Plan on live or frozen foods.

Can I keep just one Scarlet Badis?
You can, and a single male will be peaceful, but a small group with extra females is more interesting and natural.

How many Scarlet Badis in a 10-gallon?
1 male and 3–4 females is comfortable. Don’t add a second male without much more space and heavy planting.

Are Scarlet Badis good in a community tank?
Only with peaceful, slow-feeding nano species like CPDs, chili rasboras, and emerald dwarf rasboras.

Will Scarlet Badis eat shrimp?
They’ll ignore adult cherry/ghost shrimp but will eat shrimplets.

How long do Scarlet Badis live?
3–5 years with good food and water quality.

Do Scarlet Badis need a heater?
Yes — a stable mid-70s °F is much better than a fluctuating room-temperature tank.

Do they need a planted tank?
Practically, yes. Heavy planting reduces aggression, supplies micro-prey, and shows off their color.

Shop Scarlet Badis at Tropical Treasures Wyo

We hand-select healthy, brightly colored Scarlet Badis at our Cheyenne shop and make sure every fish is feeding before it goes home with you. Whether you’re building a tiny planted gem of a tank or adding a centerpiece to a nano community, we can help.

Shop Scarlet Badis · Browse all nano fish

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Tropical Treasures Wyo
190 S College Drive, Suite D, Cheyenne, WY 82007
307-369-1118

Related guides: Celestial Pearl Danio Care Guide · Chili Rasbora Care Guide · Emerald Dwarf Rasbora Care Guide · Ghost Shrimp Care Guide

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