Sanjika

Where they come from

Sanjika are fast-water cyprinids from southern Africa, showing up in rivers and lake outlets around the Lake Malawi and Zambezi systems. Think long runs, broken rock, and a ton of flow. They are migratory, they chase smaller fish and insects in open water, and they cover ground like crazy.

Setting up their tank

Give them length, current, and oxygen. Height is secondary. A bare-bones recipe that has worked for me is a long tank with a powerful river-style flow, rounded substrate, and wide open swimming lanes.

• Size: single adult 180-240 cm x 60 cm footprint (6-8 ft x 2 ft), 500-700 L+. Group of 4-6 needs 8-10 ft and 1000 L+.
• Flow: aim for 10-15x turnover with canisters and powerheads; point outlets to create a one-way run.
• Oxygen: keep surface agitation roaring. These fish crash fast if O2 dips.
• Substrate: sand or smooth rounded gravel. Sharp edges chew up their snouts.
• Hardscape: big rounded boulders to break line of sight at the ends, but leave the middle open.
• Lid: tight and heavy. They will find any gap. Tape or mesh off cable holes.

Water is pretty forgiving as long as it is clean and steady. I keep them at:

• Temperature: 22-26 C (72-79 F)
• pH: 7.2-8.2
• Hardness: mid to hard (8-20 dGH, KH 6-12)
• Nitrogen: ammonia and nitrite 0, nitrate under 20 mg/L
• Water changes: 30-50% weekly, more with heavy feeding

What to feed them

They are predators, but you do not have to run a feeder-fish operation. I start new Sanjika on movement to trigger a strike and then switch to non-live foods fast.

• Good staples: strips of tilapia or pollock, raw prawns/shrimp, nightcrawlers, crickets, BSF larvae.
• Pellets: large sinking or slow-sinking carnivore pellets. Pre-soak so they do not gulp air.
• Treats: river shrimp, silversides in moderation.

Feeding rhythm that works for me: juveniles twice a day in small portions; adults once a day or every other day. Let the current carry food past their lane and use tongs so you are not dropping chunks on the bottom for the catfish to bloat on. Add a vitamin soak once or twice a week if you feed lots of frozen.

How they behave and who they get along with

Juveniles school loosely and feel braver in a group. Adults get more territorial in open water and may spar, but they are mostly about food and space. They spook at sudden movement, then learn the feeding routine and start pacing the front like puppies.

• Best plan: species tank or a group of Sanjika in a very large river setup.
• If you must mix: choose equally fast, similarly sized, non-nippy fish that like current (large Brycinus/Alestes tetras, robust barbs, big Synodontis as bottom help).
• Avoid: anything bitey (Distichodus with an attitude), slow/long-finned fish, or small fish that become lunch.
• One big adult can work solo if the tank is not big enough for a group.

Breeding tips

This is a long-shot project. In the wild they run upstream with the rains and broadcast eggs over gravel riffles. I have not seen a confirmed home spawn. If you want to experiment, here is what people try:

• Group of 6+ with obvious size mix in a very long, high-flow tank.
• Seasonal cues: heavy water changes with slightly cooler water, ramped-up flow, big live-food feedings, extended photoperiod then a stormy dark period.
• Riffle zone: rounded gravel with egg grate or marbles so eggs drop out of reach.
• Pull adults after a spawning chase; they will eat eggs and fry.

Common problems to watch for

• Jumping and glass strikes: use a tight lid, reduce reflections, and add current to occupy them.
• Low oxygen at night: keep air and surface chop 24/7, especially after big meals.
• Parasites on new imports: quarantine 4-6 weeks; I deworm with praziquantel and levamisole and treat external flukes if needed.
• Refusing non-live food: start with motion (tongs, current), then mix in dead items; do not cave to goldfish.
• Mouth and snout abrasions: smooth decor and avoid frantic feeding frenzies.
• Bacterial fuzz after scrapes: keep water pristine; have a broad-spectrum antibacterial on hand if wounds sour.