Striped weever

Where they come from

Striped weevers (Trachinus lineolatus) are coastal, sandy-bottom ambush predators. In the wild they spend a lot of time buried with just the eyes and that first dorsal fin showing, waiting for small fish and crustaceans to wander too close.

That lifestyle is basically the whole story with this species in captivity: give them sand, give them room, and treat them like a venomous animal first and a display fish second.

Setting up their tank

Think "marine predator on a beach" rather than reef fish. They do best in a species tank or a very carefully planned predator community where nothing is small enough to be eaten and nothing is likely to pick at a buried fish.

• Tank size: bigger than you think. I would not bother under 125 gallons for an adult, and 180+ makes life easier (less pacing, more stable water, easier to keep tankmates at a distance).
• Footprint matters more than height. Go long and wide so it can choose a spot and settle.
• Substrate: fine sand, 2-4 inches. They want to bury. Coarse crushed coral can scrape them up and makes burying awkward.
• Rockwork: keep it minimal and stable. Put rocks directly on the glass or on a PVC/egg-crate base, then add sand around it. You do not want a digging fish undermining a pile.
• Flow: moderate with calm zones. They are not a "surf all day" fish. Give them an area where sand is not constantly blowing around.
• Filtration: strong and boring. Oversize skimmer, good mechanical filtration you actually clean, and a plan for heavy feeding.
• Lighting: whatever suits you, but do not blast them with reef-level lighting if the whole tank is open sand. A few shaded areas helps them settle.

A tight lid is worth it. They are not famous jumpers like some wrasses, but startled predators do dumb things, and you will startle it at some point.

What to feed them

These are sit-and-wait hunters. Once settled, most will take meaty frozen and fresh seafood, but you may have to get them going with movement at first.

• Staples: pieces of shrimp, squid, clam, mussel, scallop, and marine fish flesh.
• Frozen foods that usually work: silversides, krill, chopped prawn, carnivore blends.
• How I start them: use feeding tongs and "wiggle" the food near the snout. Sometimes a feeding stick with a thin line works even better.
• How often: small meals 3-4x/week for adults, more frequent for juveniles. They are built for big hits, not constant grazing.
• Vitamins: soak occasionally (especially if you lean on one or two foods). Variety matters more than any one product.

Do not overdo it. A weever that looks "nicely fat" is often just overfed. You want a solid, muscular fish, not a sausage that sits in the sand and breathes hard.

How they behave and who they get along with

Most of the time you will think you bought a pet hole in the sand. Then feeding time hits and it becomes a lightning-fast predator. That is normal.

They are not usually hyper-aggressive roamers, but anything that fits in the mouth is food. Also, anything that constantly pecks at the sand or the fish itself will stress it out.

• Good candidates: larger, calm fish that ignore the bottom (some larger tangs, bigger angels, some triggers with caution, larger wrasses that do not sleep-bury in the same sand bed).
• Avoid: small fish, tiny gobies/blennies, ornamental shrimp and crabs, and bottom sitters that want the same real estate.
• Watch out for: sand-sifting stars, aggressive sand-sifting gobies, and anything that will constantly bulldoze the weever's ambush spot.
• Multiple weevers: I would not try it unless you have a very large footprint and a backup plan. They are not a "pair up" species in home tanks.

If you keep it with other predators, feed in a way that does not turn the tank into a food-fight. Target feeding with tongs helps a lot. The weever is fast, but it is also a lazy ambush fish, and a boisterous tankmate can steal meals.

Breeding tips

Home breeding is not really a thing with striped weevers. In nature they spawn in open water, and the larvae are planktonic. That is a very different project than "set up a pair and watch the nest."

If you ever see courtship behavior (increased activity, chasing, rising into the water column at dusk), enjoy it, but I would not plan a system around raising the young. Focus your energy on long-term stability and feeding consistency instead.

Common problems to watch for

• Shipping and settling issues: they can come in beat up or refusing food. Give them sand, low stress, and time. Keep lighting calm the first week.
• Mouth and snout damage: often from glass-surfing or trying to bury in the wrong substrate. Fine sand and a larger footprint reduces this.
• Skin infections and abrasions: usually tied to poor substrate, sharp rock edges, or dirty water in a heavy-feeding predator tank.
• Internal parasites: if the fish eats but slowly loses weight, treat like a predator fish with a deworming plan (ideally in quarantine).
• Oxygen stress: heavy feeding + warm water + a big predator = high demand. Strong surface agitation and a skimmer that actually pulls gunk help a lot.
• Tankmate harassment: sand pickers and bullies can keep it pinned and stressed. A stressed weever is a non-feeding weever.

If you are already comfortable keeping venomous marine fish and you like oddballs, this is one of those species where the setup and your routine matter more than chasing perfect numbers. Stable salinity, clean water, a deep sand bed, and smart handling habits will make or break the experience.