Htamanthi danio

Where they come from

Htamanthi danios (Danio htamanthinus) are one of those newer-to-the-hobby danios that come out of Myanmar. They are tied to clear, moving water - the kind of small rivers and hill streams where the current is always doing something and the water stays pretty clean.

That background matters because they act like stream fish in the aquarium. If you keep them like generic "community danios" in a warm, still tank, they usually look washed out and never really settle in.

Setting up their tank

Think of your setup as "room to run" plus "clean, oxygenated water." These fish want to swim, spar, and show off. A longer tank makes your life easier than a taller one.

• Tank size: I would not do them in anything shorter than a 30 inch tank, and 36 inches long is nicer. They use the whole length.
• Group size: 10+ if you can. Small groups turn edgy and you see more fin-nipping.
• Flow and oxygen: a canister or strong HOB plus a powerhead aimed along the back wall works great. Add surface agitation.
• Temperature: keep them on the cooler side for tropicals (roughly low-to-mid 70s F). They are not a "hot" danio.
• Hardscape: smooth river stones, rounded gravel or sand, and some wood is fine. Plants are optional but helpful for breaking lines of sight.
• Lighting: moderate. Too bright with no cover can make them skittish at first. Floating plants help a lot.

Water parameters are less about chasing a specific pH number and more about stability and low waste. Keep ammonia and nitrite at zero, nitrate low, and do steady water changes. They are the kind of fish that punish sloppy maintenance.

What to feed them

They eat like danios, which is to say: with enthusiasm. In my tanks they do best on a varied diet and multiple small feedings rather than one big dump of food.

• Daily staples: high-quality small pellets or fine flakes that sink slowly
• Frozen: daphnia, cyclops, baby brine shrimp, chopped bloodworms (sparingly)
• Live (if you can): baby brine shrimp, grindal worms, daphnia
• Extras: a little crushed krill-based food can bring out color, but do not make it the whole diet

Watch the food size. Their mouths are not huge, and they are fast. Fine pellets that soften quickly tend to work better than big, hard micro sticks.

How they behave and who they get along with

They are active, alert, and a little intense. In a big group they spend a lot of time chasing and posturing, but it is usually "danio drama" rather than real damage. In a small group, that same energy gets focused on a few fish and becomes a problem.

• Best tankmates: other streamy, fast fish that like similar temps (small barbs, other danios that can keep up), hillstream loaches, hardy bottom dwellers
• Use caution with: long-finned fish (they can get nipped), very shy fish, slow feeders, tiny shrimp
• Avoid: bettas, fancy guppies, slow gouramis, anything that will be stressed by constant motion

They are also jumpers. Not always, but enough that I treat a lid as non-negotiable. Any little gap around hoses is an exit route.

Breeding tips

They are egg scatterers like most Danio. The hard part is not getting them to spawn, it is keeping the adults from eating the eggs before you ever see them.

• Condition the group with lots of small feedings (frozen/live helps).
• Set up a separate spawn tank with a bare bottom and either marbles, a mesh/grid, or a thick clump of java moss to let eggs fall out of reach.
• Use a small sponge filter and gentle flow. Keep the water clean and well-oxygenated.
• Put in 1-2 females with 2-3 males in the evening, and check for eggs in the morning.
• Pull the adults as soon as you see eggs or suspect a spawn. They will snack all day if you let them.
• First foods: infusoria or commercial fry foods for a few days, then baby brine shrimp once they can take it.

Common problems to watch for

Most issues I have seen trace back to either water quality or social stress. They look tough because they are fast, but they do not like being kept in marginal conditions.

• Faded color and clamped fins: usually stress from too-warm water, low oxygen, or not enough group size
• Fin nipping: group too small, tank too small, or not enough swimming room/line-of-sight breaks
• Rapid breathing or hanging near the surface: low oxygen, dirty filter, not enough surface movement
• Ich outbreaks after new fish: they can be sensitive to temperature swings and stress, so quarantine matters
• Wasting/skinny fish: internal parasites are not rare in wild-origin fish; quarantine and observe new arrivals closely

If you keep the tank clean, keep them cool-ish, and keep them in a real group with room to move, they are a blast. The whole vibe becomes "busy stream" and they stay on display all day.