Firefish (Fire Goby / Fire Dartfish)

1) Where they come from

Firefish (Nemateleotris magnifica) are reef fish from the Indo-Pacific—think Red Sea and across to the western Pacific. In the wild you’ll usually see them hovering a few inches above the reef, grabbing tiny food out of the water, and then zipping back to a bolt-hole the second something spooks them.

2) Setting up their tank

If you set up your tank like it’s for a “shy jumper,” you’ll be 90% of the way to success. Firefish are easy to keep once they feel safe, but they’re famous for launching themselves through tiny gaps in lids.

They don’t need a massive tank, but they do like a little “runway” to hover and dart. A 20–30 gallon is a comfy starting point for one, bigger is always easier for stability. The real key is rockwork with multiple caves/crevices so they can pick a home base.

• Tank size: 20+ gallons for one (30+ feels nicer long-term); bigger if you want tankmates
• Aquascape: rockwork with several tight hidey-holes and an open area in front for hovering
• Flow: moderate—enough to keep food moving, not so much they get blasted off their perch
• Lighting: whatever your reef needs; the fish doesn’t care much as long as it has cover
• Substrate: sand is nice but not mandatory; they’re not sand sifters like some gobies

3) What to feed them

Firefish are planktivores—tiny stuff drifting by is their whole vibe. Most will learn frozen foods quickly, but new ones can be shy at first and let bolder fish steal everything.

• Frozen: mysis (small pieces), brine (better if enriched), finely chopped seafood blends
• Small pellet/flake: only after they’re settled; pick a small pellet that sinks slowly
• Live (great for new/shy fish): live baby brine or copepods if you have access

Watch their belly line. A well-fed firefish looks gently rounded, not pinched. If it’s always hiding and staying skinny, that’s usually a competition problem (or it hasn’t settled yet).

4) Behavior and tankmates

They’re peaceful, a little nervous, and honestly kind of adorable. Most of the day they hover in the water column like a tiny kite, then “boop” back into the rocks if you walk by too fast.

Best tankmates are other calm reef fish that won’t chase them out of their spot or outcompete them at every meal. Firefish usually get bullied long before they’ll ever bully anything else.

• Good tankmates: clownfish (not overly aggressive ones), small wrasses that aren’t jerks, banggai cardinals, royal gramma (usually), small gobies/blennies
• Use caution: dottybacks, big/territorial damsels, aggressive clowns, hawkfish (can harass), large wrasses
• Avoid: predators that can fit them in their mouth, and super pushy feeders in small tanks

If you really want more than one, do your homework and have a backup plan (divider, second tank, ability to rehome). One firefish is a stress-free win.

5) Breeding tips (the hobby reality)

They can spawn in captivity, usually in a bonded pair with a chosen cave. You might see courtship and then eggs guarded in the burrow/crevice. Raising the babies is the hard part—larvae are tiny and need live plankton foods (rotifers/copepods) and a dedicated rearing setup.

6) Common problems to watch for

• Jumping: the #1 killer—cover every opening, especially after lights out or during tank changes
• Starving in a “busy” community tank: they’re polite eaters; target feed if needed
• Stress/hiding: often from aggressive tankmates, too much sudden movement, or not enough rock cover
• New fish not eating: offer smaller foods (live if you can), dim the lights, and keep the area calm
• Parasites (ich/velvet): they’re not uniquely prone, but they’re sensitive to stress—quarantine helps a lot
• Getting blown around: overly strong/direct flow can keep them pinned behind rocks