Goonch catfish

Where they come from

Goonch are big river catfish from South Asia. Think fast, cold-to-cool, rocky rivers like the Ganges and Indus drainages, with seasonal floods and roaring currents. They park themselves on the bottom like a shaggy doormat and wait for food to wash past.

Setting up their tank

Treat a goonch like a small river project, not just a big aquarium. Long footprint, huge filtration, and heavy current matter way more than fancy decor.

• Size: think 800-1500+ gallons with a 10-12 ft length if you want to keep one into adulthood. A temporary 300-400 gal works only for a fast-growing juvenile.
• Footprint: wide and long beats tall. They sprawl on the bottom and like straight runs to cruise.
• Flow: strong, laminar river-style current. Aim for 10-20x turnover per hour with big pumps or river manifold. Lots of surface agitation.
• Oxygen: keep it high. Big venturis, spray bars, or air rings under the flow. They sulk in low O2.
• Temperature: 68-75 F (20-24 C) is the sweet spot. They handle slightly cooler. Avoid long spells above 77 F (25 C).
• Water: pH 6.8-7.8, moderate hardness. Zero ammonia and nitrite. Keep nitrate as low as you reasonably can (under 20 ppm is a good target).
• Substrate: smooth sand with rounded cobbles and big river rocks. Skip sharp edges; they scrape easily.
• Decor: open lanes to sit in the flow, a couple of shaded arches or big PVC sections. They do not need caves like plecos.
• Lid: tight and heavy. A spooked goonch can launch like a torpedo.

Filtration needs to be pond-level. Big sump with lots of mechanical prefilter (brushes, filter socks, or drum filter) before your bio media. Expect messy, oily food and heavy waste. I backwash daily and swap prefilters 2-3 times a week. Water change 30-50% weekly, more if you feed heavy.

What to feed them

They are carnivores and very food-motivated once they settle. Getting them onto clean, non-live foods early makes life easier for you and safer for them.

• Staples that work: thawed silversides, tilapia/salmon chunks (skin off), prawn/shrimp, mussel, nightcrawlers, and quality carnivore sticks (Hikari Massivore/Carnivore, NorthFin, etc.).
• Feeding schedule: juveniles small amounts daily; subadults every other day; big adults 2-3 times per week. Watch the belly line, not the calendar.
• Training tip: offer with long tongs in the current so it looks like drift. They usually switch off live food within a week or two.
• Avoid: feeder fish (parasites, thiaminase, fatty liver), goldfish, rosy reds, and only-anchovy/smelt diets. Mix it up.
• Supplements: a quick vitamin soak once a week is handy if you mostly feed fish and shrimp.

How they behave and who they get along with

Picture a big, flat ambush cat that naps in the current, then explodes forward for food. Mostly crepuscular, but they learn your schedule. They are not community fish. Anything bite-sized is a snack, and even large tankmates get bullied or slammed into things during feeding.

• Best plan: single-specimen setup.
• If you must try tankmates: only very large, fast, river-adapted fish that like cool water and current. Think big mahseer or similar tor species, big hardbody barbs, or large riverine stingrays if temps match and footprint is huge.
• Skip: slow fish, fish that need warm water, bottom dwellers that compete for the same lane, delicate species, and anything you are attached to.

Breeding tips

Realistically, you are not breeding goonch at home. They are migratory river spawners keyed to monsoon cycles and long runs of fast water. Sexing is uncertain without mature pairs, and I have never seen a credible home-aquarium spawn report. If you hear about captive production, it is usually from large facilities or ponds in their native range.

Common problems to watch for

• Low oxygen: fast gilling, hanging at the surface, or parking under a return. Add air and flow immediately.
• Heat stress: listless fish and rapid breathing above 77 F. Cool the room or water, increase aeration.
• Scrapes and mouth abrasion: they slam rocks during feeding. Use rounded decor and feed away from sharp edges.
• Parasites and bacteria from live feeders or wild bait: quarantine food sources or skip live feeders altogether.
• Nitrate creep: big carnivores drive nitrate up. Heavy prefilter, big water changes, and consider a denitrifying section or plants in the sump.
• Refusal to eat after a move: keep lights low, flow strong, and offer worms or prawn on tongs in the current. Do not chase or poke.
• Jumping and lid strikes: startled fish hit lids hard. Keep the room calm, lights on a schedule, and lids secured.

Medication in huge volumes is expensive and risky. I focus on water, oxygen, and temperature first. Salt can help with minor scrapes, but go slow and measure. For anything more serious, I move the fish to a large hospital tub with heat and heavy air, treat there, and keep the display pristine.