Mweru elephantfish

Where they come from

Mweru elephantfish are from Lake Mweru and the Luapula River on the DR Congo-Zambia border. Think slow margins with fine sand, leaf litter, and tangled roots. The water is usually soft and a bit tea-stained. They use a weak electric field to find food in that murky, cluttered world.

Tank setup

Plan for a roomy, quiet setup. A single adult does best in at least a 4-foot tank (around 250 liters or more). They spook easily, so give them space and lots of cover.

• Temperature: 24-27 C
• pH: 6.0-7.4
• Hardness: soft to moderately soft (roughly 2-8 dGH)
• Flow: gentle, steady, with good oxygenation
• Lighting: low to moderate; they relax under dim light and tannins

Use fine sand. They sift constantly with that long snout, and gravel will chew it up. Add wood, leaf litter, and a few snug tubes or caves. A tight lid is a must; they will jump if startled.

Filtration should be strong but not blasting. I like a canister with a spray bar and a pre-filter sponge on the intake so they do not suck up sand. Keep things stable and clean. Weekly 30-50% water changes with matched temp and similar softness work well. A bit of leaf litter or botanicals helps them settle.

What to feed them

In nature they pick tiny worms, insect larvae, and crustaceans at dusk. In the tank, most start on live foods and can be weaned to frozen. Pellets are hit-or-miss.

• Go-to foods: live blackworms, live or frozen bloodworms, frozen mysis, chopped earthworms (well-rinsed)
• Extras: finely chopped prawn, soft gel foods that soften in water
• Less useful as staples: adult brine shrimp (too light on nutrition), dry pellets (some individuals never take them)

Feed at lights-out or under very dim light. Target feeding with a turkey baster works great. I usually mix a few live worms with frozen to start the transition. Keep portions small, 2-3 times daily at first, and siphon leftovers so the sand stays clean.

How they behave and who they get along with

They are shy, crepuscular fish that map the world with electricity. Once settled, they cruise the bottom and sift sand. Sudden light or banging near the tank will send them darting.

• Good matches: calm midwater schoolers that are not nippy and do not outcompete for food; a single specimen tank is often the easiest path
• Borderline: small, peaceful bottom fish that feed during the day and leave the sand at night; watch for food competition
• Avoid: barbs and other fin nippers, cichlids that guard territory, loaches and active catfish that bulldoze the bottom, knifefish, electric catfish, and other mormyrids in small tanks

Breeding tips

This species is rarely bred at home. Sexing is tricky without experience, and courtship involves electric signaling. If you want to try, you will need a large, very quiet tank, soft water, heavy feeding, and seasonal cues.

• Condition a compatible pair or group on rich live and frozen foods.
• Provide deep sand, mops or fine plants, leaf litter, and very dim light.
• Simulate the rainy season: several large water changes over a week using slightly cooler, softer water.
• If eggs appear, remove adults or move the eggs; adults may eat them.
• Fry would start on tiny live foods (infusoria, then freshly hatched baby brine and microworms).

Common problems to watch for

• Not eating: new fish often ignore prepared foods. Offer live blackworms or bloodworms at night to get them started, then mix in frozen.
• Snout injuries: happen on gravel or sharp decor. Switch to fine sand and keep the front glass algae-free so they do not scrape while probing.
• Medication sensitivity: copper, formalin, and many dye-based meds hit them hard. Treat in a hospital tank with products safe for scaleless fish and crank up aeration.
• Nitrate creep: they sulk and go off food when nitrate creeps high. Aim to keep it low with regular water changes and light feeding.
• Bullying or food theft: if tankmates eat everything midwater, the elephantfish slowly starves. Rework the stocking or feeding method.
• Light stress: bright, open tanks make them pace and dash. Add cover and dim the lights.
• Jumping: they bolt through tiny gaps. Cover every opening.
• Parasites from live foods: source live worms carefully and rinse them well before feeding.