Tancho betta (Tancho Pair)

Two crimson crowns on snow—small, aggressive sovereigns of hard water.

Shop our hand-selected Tancho Pair — striking 4–5cm red-crowned koi with bold, boisterous personalities. Ideal for high-pH ponds and large tanks. Order online today.

• Water Conditions: The Tancho is a hardy, adaptable fish, but this pair is at its best in alkaline water with a pH held between 7.5 and 8.5 — which is why we list them as a high-pH livestock line. Keep the carbonate hardness steady (KH 4–10 dKH) so the pH does not swing overnight, and aim for a temperature of 18–24°C, rising to a stable 22–25°C during the summer growing months. Ammonia and nitrite must read zero at all times, with nitrate kept below 40ppm through regular partial water changes. These are active, oxygen-hungry fish with a heavy bioload even at 4–5cm, so run a mature filter rated well above the tank volume, add an air pump or surface-agitating return, and never introduce them to an uncycled system. If your tap water is soft or acidic, buffer it before the fish go in rather than after — a sudden pH drop is far more dangerous to a Tancho than a steady, slightly alkaline reading.
• Suitable Tank Mates: Treat this pair as boisterous, food-driven and distinctly pushy. They are listed as aggressive because they bully slow, long-finned or timid companions, chase at feeding time, and will happily swallow anything that fits in their mouths. House them with robust, fast-swimming species of a similar size — large barbs, big danios, weather loach, or other koi and pond fish of comparable bulk — in a tank or pond with serious swimming room. Avoid fancy goldfish, small tropicals such as neons and guppies, slow bottom-dwellers, and anything with trailing fins that invites nipping. Two Tancho kept together will squabble over food, so feed across several points in the tank to spread the aggression. Never mix them with aggressive cichlids or territorial bottom fish, and if you are adding to an existing pond, watch the first 48 hours closely for chasing and fin damage.
• Feeding Habits: Tancho are omnivorous, greedy and constantly foraging, which makes feeding the easiest and most enjoyable part of keeping them. Offer a quality floating koi pellet as the staple, sized to the mouth, and supplement two or three times a week with live or frozen bloodworm, brine shrimp, daphnia, chopped prawn and blanched vegetable matter such as spinach, courgette or peas. Feed two to three small portions daily — only what they clear in a few minutes — and scale back sharply as temperatures fall below 12°C, stopping altogether in the depths of winter when the fish become dormant. Because these are competitive feeders, never rely on food reaching shy tank mates; use a feeding ring or target feed with tongs. Remove any uneaten food after five minutes to protect water quality, and avoid high-protein growth foods in cool water, which can lead to digestive problems and fat accumulation.
• Care Requirements: Coming to you at 4–5cm, these are juveniles with decades of life ahead — expect them to reach 30–60cm and plan space accordingly, because a Tancho pair will outgrow most aquariums within a couple of years. Float the bag to equalise temperature, then drip-acclimatise over 45–60 minutes and net the fish into the pond rather than pouring transport water in. Quarantine new arrivals for two to four weeks where possible, and keep a jump guard on any indoor tank. Carry out 20–30% weekly water changes with dechlorinated, temperature-matched water, vacuum debris from the base, and keep filters clean but never sterile. Inspect the red crown and flanks weekly for ulcers, flukes, fin rot or white spot, and watch for flashing and clamped fins as early warning signs. Koi are also notorious for eating plants and digging, so choose robust planting or none at all. With steady water, generous filtration and moderate feeding, a Tancho pair will reward you with decades of colour and personality.