Yellowtip halfbeak

Where they come from

Yellowtip halfbeaks (Hemiramphus marginatus) are surface fish from warm coastal marine waters. Think sheltered shorelines, bays, and areas where there is a mix of current, wave action, and floating food. They are built to cruise the top few inches all day, snatching tiny prey off the surface.

Setting up their tank

Give them length and calm at the surface. They are fast, nervous, and they spook hard. A long tank (4 ft/120 cm minimum, longer is better) makes a massive difference. Depth is less important than having room to build speed without smashing into glass.

• Tank size: I would not bother under 75-90 gallons for a group; bigger if you want multiple males
• Cover: tight lid with no gaps - they jump like missiles, especially at night
• Surface flow: gentle to moderate; avoid blasting the top layer with a powerhead
• Oxygen: high - good gas exchange, skimmer running, and plenty of turnover
• Lighting: not crazy bright at first; let them settle, then ramp up

I like a "coastal" aquascape: rockwork pushed back or to the sides, open swimming lane along the front, and some surface structure so they do not feel exposed. You can use patches of macroalgae (like Caulerpa or Halimeda) if your setup allows it, or even a small section of floating-style cover (plastic craft mesh tucked under the rim works) to break up reflections and calm them down.

• Temperature: 24-27 C / 75-81 F
• Salinity: 1.023-1.026 (pick a number and hold it there)
• pH: 8.1-8.4
• Nitrate: low (single digits is where I aim); they show stress fast in dirty water

Quarantine is tricky because they panic in bare tanks. If you can, use a larger QT with a lid, dim light, and something at the surface for security. Also, pad any hard edges near the waterline and keep equipment cords and lid gaps sealed.

What to feed them

These are surface micro-predators. Most new arrivals do not recognize pellets right away, and they can starve in a tank full of food if the food sinks. You want foods that hover or float and you want to feed small amounts multiple times a day at first.

• Best starters: live or enriched frozen baby brine, mysis (small), calanus, copepods
• Surface-friendly options: floating marine pellets (small), crushed flakes, gel foods formed into tiny bits
• Treats: live blackworms (if you can source safely), tiny live shrimp, small insects (only if you trust the source)

Watch their bellies. A yellowtip halfbeak that is eating well looks sleek but not pinched, and you will see them doing quick surface strikes throughout the day. If they hang in one corner and ignore food, something is off - usually stress, bullying, or water quality swings.

How they behave and who they get along with

They are schooling-ish, but not in the tight, synchronized way people imagine. A small group spreads aggression and makes them bolder. Keep more than one if you can, and give them room so they are not constantly in each other's faces.

• Group size: 5-8 is a nice number if your tank can handle it
• Temperament: skittish, fast, can be pushy at the surface during feeding
• Day-to-day: they patrol the top, then bolt if something startles them

Tankmates need to pass two tests: they cannot outcompete them at the surface, and they cannot harass them into the lid. Avoid anything nippy or anything that does "food tornado" feeding that makes halfbeaks afraid to come up.

• Usually works: calm midwater fish, peaceful reef fish that feed lower in the water column, small to medium wrasses that are not bullies
• Often a bad idea: aggressive damsels, dottybacks, triggerfish, large wrasses with attitude, anything that chases or strikes upward
• Also risky: big surface feeders like some anthias groups or boisterous chromis that swarm the top

Breeding tips

Breeding in home marine tanks is possible but not something I would promise. The bigger challenge is getting adults settled long-term and feeding them heavily without wrecking water quality. If you do get courtship, it happens near the surface and around structure.

• Conditioning: heavy feeding with small meaty foods, multiple feedings per day
• Environment: stable salinity and temperature, calm surface areas with some cover
• Egg/fry safety: adults will pick off anything small they notice at the surface

Common problems to watch for

Most yellowtip halfbeak losses trace back to three things: jumping, not eating, and stress injuries. They are hardy once settled, but the first few weeks are make-or-break.

• Jumping: the #1 killer - lids, sealed gaps, and calm tankmates
• Starvation: they ignore sinking food; you have to feed for the surface
• Mouth/jaw damage: from glass surfing, panic darts, or fighting at the surface
• Parasites: especially on new wild fish - watch for flashing, heavy breathing, and refusal to feed
• Surface film: they feed at the top, so keep the surface clean with skimming and good flow

One last practical thing: acclimate them slowly and keep the lights low on day one. I also like to feed a tiny amount within a few hours of introduction (something they cannot resist, like calanus). Seeing them strike at food early is usually the sign you are on the right track.