Brazilian codling
Urophycis brasiliensis
The Brazilian codling features a slender, elongated body with a mottled brown to olive coloration and distinct, long pectoral fins.
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About the Brazilian codling
This is a demersal (bottom-loving) marine codling from the Southwest Atlantic that hangs around the continental shelf and cruises sandy/rocky bottoms looking for food. It is basically a cool, mottled little gadiform with that classic codling vibe - elongated body and a chin barbel - and it is mostly of interest as a food/fishery species rather than something you would ever see in home aquariums.
Also known as
Quick Facts
Size
58.6 cm TL
Temperament
Semi-aggressive
Difficulty
Expert
Min Tank Size
300 gallons
Lifespan
10-20 years
Origin
Southwest Atlantic (southeastern Brazil to Argentina/Uruguay and Falkland Islands)
Diet
Carnivore - crustaceans, mollusks/worms, and small fishes
Water Parameters
20.6-25.5°C
7.8-8.4
8-12 dGH
Need a heater for this species?
This species needs 20.6-25.5°C in a 300 gallon tank. Use our heater calculator to find the right wattage.
Calculate heater sizeCare Notes
- Give it a big, coldwater marine setup with real floor space (think 180+ gallons for an adult) and strong oxygenation - they hang near the bottom and sulk when flow and O2 are weak.
- Keep temps on the cool side: 55-64F (13-18C) is where they act normal; 70F+ is where you start seeing stress, fast breathing, and infections creeping in.
- Run full-strength seawater (SG 1.023-1.026), pH 8.0-8.3, and keep nitrate low (under ~20 ppm) because they are messy eaters and big protein in = big waste out.
- Do a sand bed or smooth substrate and give dark caves/overhangs - they like to wedge in and will scrape themselves up on sharp rockwork or rough PVC.
- Feed like a predator: chunks of marine fish, shrimp, squid, clam, and silversides; start with tongs at dusk and get them onto 2-3 solid meals a week instead of daily snacking.
- Skip tiny tankmates - anything that fits in the mouth is food; also avoid hyper-aggressive bruisers (big triggers, large morays) that will harass them into hiding and not eating.
- Watch for mouth/jaw injuries and skin scrapes (they ram decor when spooked), and quarantine hard because coldwater parasites and bacterial issues can blow up fast when they are stressed.
- Breeding in home aquariums is basically a unicorn - they are seasonal spawners in nature and you would need big volume, stable cool temps, and a plan for pelagic eggs/larvae, so don’t buy a pair expecting babies.
Compatibility
Good Tankmates
- Medium to larger, hardy reef-safe-ish fish that can hold their own, like tangs and rabbitfish (theyre active, not easy to bully, and usually too big to be seen as food)
- Bigger wrasses (think Coris-type or other robust wrasses) that are always on the move and not intimidated by a semi-pushy tank mate
- Dwarf to medium angels (Centropyge and similar) in a roomy tank - theyre generally tough enough and not slow, just watch the first week for posturing
- Chunkier damsels or chromis groups in a big setup - theyre quick and street-smart, so they dont just sit there and get picked on
- Similar-sized, non-delicate bottom area fish that arent tiny bite-sized snacks - think sturdier blennies or larger gobies that can bolt into rockwork
- Other semi-aggressive fish of similar size (like some triggers that arent total terrorists), as long as you give lots of rockwork and personal space
Avoid
- Tiny fish like small gobies, small blennies, juvenile chromis, or anything thats basically 'snack sized' - these codling-types are opportunistic and will eventually test that mouth size
- Slow, fancy-finned or timid fish like firefish and cardinals - they dont deal well with a semi-aggressive neighbor and can get stressed into hiding and not eating
- Super nippy or hyper-territorial stuff like psycho damsels or dottybacks in tight quarters - you end up with constant chasing and shredded fins
- Very small crustaceans (tiny shrimp) or anything you really dont want eaten - if it fits, it disappears, especially at feeding time or after lights out
Where they come from
Brazilian codling (Urophycis brasiliensis) is a Western Atlantic fish from the Brazilian/Uruguayan coast down into cooler South Atlantic waters. Think continental shelf, deeper reefs and rubble zones, and a life spent hovering close to the bottom looking for something meaty to inhale.
They are not a common aquarium fish for a reason: they are a coldwater, deep-ish, predator type that does not forgive shortcuts. If you have only kept tropical reef fish, this is a totally different project.
Plan for coldwater marine. If you try to run this fish at typical reef temps, you will be chasing problems nonstop (oxygen, appetite swings, infections). A chiller is not optional.
Setting up their tank
Give them space and stability first, decor second. These fish do best in a big, mature system with strong filtration and lots of dissolved oxygen. They spend a lot of time near the bottom and will wedge into structure, so build with that in mind.
- Tank size: I would not bother under 180 gallons for an adult, and bigger is better if you want it to settle in and feed confidently.
- Temperature: coldwater range. Aim around 50-60F (10-16C) unless you have a reliable local reference for your collection area.
- Salinity: normal marine (around 1.023-1.026). Keep it steady, no swingy top-offs.
- Flow and oxygen: brisk turnover plus serious surface agitation. In cold systems you can still run low oxygen if the surface is calm.
- Filtration: heavy mechanical plus oversized bio. They are messy eaters and their food is rich.
- Substrate and structure: sand or fine gravel with plenty of rock piles and caves. Make sure it cannot collapse if the fish bulldozes around.
Use big, stable rockwork on the glass bottom or on supports, then add substrate around it. Codling will nose into gaps and can undermine a pile that looked solid on day one.
Lighting does not need to be fancy. Mine acted calmer under subdued lighting with shaded areas. If the tank is bright and bare, they tend to stay hidden and feed poorly.
Cover the tank. They are not classic jumpers like wrasses, but startled bottom predators can launch surprisingly well, especially during netting or if a pump kicks on/off.
What to feed them
This is a carnivore that wants real food. In the wild it is eating fish, shrimp, crabs, worms - anything it can ambush. In captivity, you want a varied, marine-based diet and you want to avoid turning it into a one-food addict.
- Staples: chunks of marine fish (smelt, silversides, hake, etc), squid, shrimp, clam, mussel, scallop.
- Good variety items: krill (as a treat), marine worms if you can source clean ones, crab pieces.
- Prepared: some individuals take sinking carnivore pellets, but do not count on it at first.
- Avoid: freshwater feeder fish, goldfish, and fatty freshwater meats. They foul water and are nutritionally wrong over time.
Target feeding works best. Use long tongs or a feeding stick and place food near the fish. If you just broadcast chunks, tankmates will steal most of it and the codling will learn to lurk and sulk.
Start new arrivals on scent-heavy foods like clam or shrimp, then rotate in fish and squid once it is eating. If you only offer one favorite early on, it can refuse everything else later.
Feed adults a few times a week rather than stuffing them daily. They are built for big meals and rest days. Overfeeding is the fastest way to ruin water quality in a cold system.
How they behave and who they get along with
They are a sit-and-wait predator. Most of the day you will see a head poking from a cave, then at feeding time it turns into a vacuum cleaner with fins. They are not a display fish in the "always swimming" sense, but they have a cool, calm presence once settled.
Tankmates need to match three things: temperature, size, and attitude. Anything small enough to fit in its mouth is food, not a friend. Anything too aggressive will keep it pinned in hiding and you will never get it feeding right.
- Good direction: other coldwater species that are chunky, not nippy, and not super competitive at feeding time.
- Avoid: small fish, ornamental shrimp/crabs, and fast food-thieves that swarm the surface.
- Also avoid: fin-nippers and "busy" fish that constantly invade its cave space.
Assume it will eat any crustacean you care about. Even if it ignores a cleaner shrimp for a month, one night it will decide it is on the menu.
They can be kept singly. I would not attempt multiples unless you have a very large system with multiple cave zones and you are prepared to separate them if one starts claiming the whole bottom.
Breeding tips
Realistically, breeding Brazilian codling in home aquariums is not something most of us will pull off. In the wild, codlings spawn in the water column with pelagic eggs and larvae. That means big seasonal cues (temperature shifts, photoperiod changes) and then tiny live foods for larvae.
If you ever do want to try, your best first step is simply keeping one fat, healthy adult for years with seasonal temperature and day-length changes. If you cannot keep weight on the fish long-term, spawning is not going to happen.
Common problems to watch for
Most issues I have seen come from three things: warm water, dirty water, and stress from bad tankmates. Fix those and you dodge a lot of the usual headaches.
- Refusing food after arrival: very common. Give it hiding spots, dim the tank, and offer clam/shrimp with tongs. Do not keep "testing" it by chasing it with the net.
- Rapid breathing or hanging in high flow: often oxygen/temperature related. Check temp, surface agitation, and any clogged intakes.
- Mouth injuries: they strike hard at tongs and rockwork. Use soft-tipped tongs and feed away from sharp stone edges.
- Parasites from wild collection: flukes and internal worms can show up. Quarantine is your friend, and a fish that keeps losing weight despite eating deserves investigation.
- Bacterial infections and fin rot: usually follow stress or poor water. Coldwater does not mean germs are gone - they are still there.
Do not "medicate the display" casually in a cold marine predator tank. Many meds behave differently at low temps, and you can crash your biofilter fast. Quarantine and targeted treatment beats panic dosing every time.
If you take anything from this: run it cold, run it clean, and feed it like a predator, not like a reef fish. Get those three right and the Brazilian codling is a really rewarding oddball to keep.
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