Ember tetra

1) Where they come from

Ember tetras come from slow, warm blackwater streams in Brazil (Araguaia/Tocantins area). Think tea-colored water, lots of leaf litter, roots, and gentle flow. That “soft and tannin-stained” vibe is why they look extra orange in a well-set-up tank.

2) Setting up their tank

Give them a calm, planted setup and they’ll be out all day. I’ve kept them in everything from a 10 gallon to a 20 long—bigger just makes schooling behavior look better and keeps water steadier.

• Tank size: 10g minimum for a small group, 15–20g is nicer if you want a proper school
• Group size: 10+ if you can; 6 works, but 12 looks amazing
• Filter/flow: gentle sponge filter or a baffled HOB; they don’t love being blasted around
• Scape: live plants (especially floaters), driftwood, and dark substrate if you want max color
• Lighting: moderate; floaters help them feel secure and show better color

For water, they’re pretty forgiving as long as you keep it stable and clean. Warm is their happy place. If your tap is on the harder side, they usually adapt fine—just don’t swing parameters around chasing a number.

3) What to feed them

They’ll eat almost anything, but their mouths are tiny. Big flakes get chewed and spit, and a lot ends up as mulm. Small foods make a big difference in growth and color.

• Daily staple: micro pellets, crushed flake, or nano granules
• Best “make them glow” foods: baby brine shrimp, daphnia, cyclops
• Easy frozen: brine shrimp, cyclops, and finely chopped bloodworms (not too much)
• Feeding style: 1–2 small feedings; watch that everyone gets some

4) Behavior and tankmates

Embers are peaceful, a little shy at first, and they look best in a bigger group. In a planted tank they’ll loosely school and “spark” around the midwater. If you only keep a few, they tend to hide and lose color.

• Great tankmates: other small calm fish (chili rasboras, small pencilfish), corydoras, otocinclus, small plecos, peaceful gouramis (like honey gourami), and most shrimp (adult shrimp are usually fine)
• Use caution: long-finned fish that get nipped (rare with embers, but stressed fish do odd things), very active danios, bigger tetras, or anything that treats them like snacks
• Avoid: large cichlids, adult angelfish, and any predator-type fish—embers disappear

5) Breeding tips (if you feel like trying it)

They’re egg scatterers and honestly not that hard if you set up a little breeding tank. In the main display, the eggs and fry usually get eaten before you ever notice.

• Setup: 5–10g with a sponge filter, heater, and a clump of java moss or a spawning mop
• Water: slightly softer/acidic helps, warm (around the upper 70s°F)
• Conditioning: feed small live/frozen foods for a week
• Spawning: add a conditioned pair or small group in the evening; eggs often show up by morning
• After eggs: pull adults or move the eggs—adults won’t babysit
• Fry food: infusoria/microworms first, then baby brine shrimp once they’re big enough

6) Common problems to watch for

Most ember tetra issues come down to stress (too few fish, too bright/bare tank, too much flow) or slow water quality creep (overfeeding, dirty substrate). They’re hardy, but they’re small—little problems hit them quicker.

• Pale color/hiding: group too small, tank too open, or lighting too harsh
• Shredded fins: usually nippy tankmates or a cramped group; sometimes filter intake/strong current
• Skinny fish: food too big, fast tankmates outcompeting them, internal parasites if it persists
• Ich after adding new fish: they can catch it fast—quarantine new arrivals if you can
• Random losses in a new tank: immature biofilter; they hate ammonia/nitrite