Care Guide for Rummy-Nose Tetras — Aquatic Canary in the Coal Mine

The rummy-nose tetra is a long-time favorite in the hobby because of its unique colors and tight schooling behavior, which is why it ranks in the top 20 fish sold at our retail fish store. This outgoing fish gets its common name comes from the reddish flush on its face, and there’s nothing like seeing a large group of gorgeous redheads darting back and forth amidst an emerald forest of live aquarium plants. Learn more about this dazzling tetra and how to best bring out its crimson colors.

What are Rummy Nose Tetras?

These 2-inch (5 cm) South American characids have a torpedo-shaped profile typical of tetras. While the body is shiny and silvery, the snout is red-orange and the tail has horizontal, white and black striping. Other color variants, such as albino and golden types, are also available. The three main species that are commonly sold as rummy-nose tetras include:

• Hemigrammus rhodostomus (true rummy-nose tetra): standard red nose and striped tail
• Hemigrammus bleheri (firehead or brilliant rummy-nose tetra): more redness on the head that goes past the gill plate and sometimes has a tapered, diamond shape
• Petitella georgiae (false rummy-nose tetra): the middle black stripe on the tail extends onto the back half of the body and looks like a short, horizontal line

Hemigrammus rhodostomus or true rummy-nose tetra

Besides their striking appearance, they are known for three interesting characteristics. First off, they tightly school together and change directions like a giant flock of birds. This behavior is useful for confusing predators, who will have a tougher time pinning down an individual tetra that is surrounded by a swarm of doppelgangers. Secondly, they can live in higher-than-normal temperatures in the low to mid 80s°F and therefore are often paired with other warmer water fish like discus, German blue rams, and Sterbai corydoras. Finally, they often get called the “canary in the coal mine” of aquariums because their noses lose their color when stressed. This visible indicator can help warn you of bad water quality, low temperatures, disease, bullying, or other problems in the aquarium. This happiness gauge is great for both beginners and veterans because you can instantly tell at a glance when things are going well or not.

Are rummy-nose tetras hardy? Because of their sensitivity to sources of stress, many people do not recommend them for new fishkeepers. In our experience, they are adaptable to a wide range of parameters and can be kept by beginners. The key is to buy healthy specimens and always quarantine them. We have sold thousands of rummy nose tetras at our retail fish store, and they sometimes arrive with ich (white spot disease) or bacterial infections. Look for fish that have red noses, slightly rounded bellies, good activity level, and no white spots or other symptoms. If their noses are pale, they may have just arrived a couple days ago or were recently chased around with a net, so wait half an hour or come back another day to see if they color up again. When you take them home, it is quite normal for them to “play dead” in the fish bag, but once you place the bag on a solid surface, they will easily right themselves again. Make sure to quarantine them in a separate hospital tank and consider proactively treating them with broad-spectrum medications. Once they pass the quarantine stage with a clean bill of health, then you can add them to your main display aquarium and fully enjoy their beauty. When kept in a seasoned aquarium with good husbandry, they can live up to 5 years or more.

Hemigrammus bleheri or firehead tetra

How to Set Up an Aquarium for Rummy-Nose Tetras

The care requirements for these three species are very similar because they all come from blackwater rivers and streams in the Amazon basin. The water in these areas is very soft and acidic from fallen leaves, rotting wood, and other organics. However, we have found that they can do well in pH levels of 5.5–7.5 with soft to moderately hard GH. Despite their small size, a 20-gallon tank or bigger is more suitable because rummy nose tetras are active schooling fish that prefer a longer tank to swim back and forth. Plus, they enjoy warmer waters between 74–84°F (23–29°C), so get an aquarium heater if needed.

If you want to make a biotope setup that imitates their natural environment, cover the ground with catappa leaves, driftwood, and botanicals like alder cones. These organic materials will break down over time, tinting the water brown and gradually lowering the pH. Personally though, we find that their red and silver colors look amazing in a planted aquarium with lots of greenery. A darker background and substrate seem to make the tetras stand out even more.

How many rummy nose tetras should be kept together? While six is the typical number suggested for a school of fish, rummy-nose tetras need a bigger group to see their special swimming behavior. Get at least 8–12 tetras and you won’t regret it.

What fish can live with rummy nose tetras? They get along with any peaceful community fish that are similar-sized, such as other tetras, rasboras, and corydoras. Their bold personality makes them great dither fish for shy or territorial fish like Apistogramma dwarf cichlids. And as mentioned before, you can keep them at higher temperatures with other warmer water species. Conversely, do not put them with cooler water fish because of the mismatched temperature requirements. Like most fish, they will opportunistically snack on baby shrimp and fry, but they tend to leave the adult dwarf shrimp and snails alone.

Petitella georgiae or false rummy-nose tetra in a biotope aquarium

What Do Rummy Nose Tetras Eat?

These omnivores are so fun to feed because they’ll swim all over the tank to chase down almost any community fish food you drop in the tank. In fact, since they are such eager eaters, we always use them to test out new foods in our retail fish store. Ideally, you want to feed smaller foods that can fit in their small mouths, such as baby brine shrimp, nano pellets, and daphnia. To bring out their rosy blush, offer fish foods that contain naturally color-enhancing ingredients, like the krill in Xtreme Krill Flakes and salmon in Easy Fry and Small Fish Food. The key is to provide a variety of different options to avoid potential nutrient deficiencies in their diet.

How to Breed Rummy-Nose Tetras

In terms of sexing these tetras, the males are slenderer in shape and the females tend to have rounder bodies, especially when full of eggs. To ensure you have both sexes, start with a big breeding group of at least six fish. Ideally, use a mature, 10-gallon aquarium as the breeding tank so it has plenty of mulm and microfauna for the fry to feed on. The eggs hatch best in very soft water and acidic pH less than 6.5. Add a heater to raise the temperature to the 80s°F and a sponge filter with gentle flow that won’t suck up the babies. These egg scatterers will predate on their own young, so get some plastic craft mesh to cover the bottom and allow the eggs to fall through while stopping the adults. Put java moss, DIY spawning mops, or other dense and fluffy plants under the mesh as added protection. 

Condition the adults for breeding by feeding lots of high-quality foods like live baby brine shrimp and then put them in the breeding tank. While the eggs don’t need to be kept in total darkness like certain species of tetras, some hobbyists recommend keeping the lights off in case of light sensitivity. Remove the adults after a few days, especially if you notice eggs or fry. Start the newborns with tiny foods like infusoria, live vinegar eels, and powdered fry food, and then switch them over to live baby brine shrimp as soon as they’re big enough to increase their growth and survival rate.

A school of Hemigrammus rhodostomus in a planted community tank

Hopefully we’ve convinced you to try this fantastic schooling fish in your next community tank. While we do not ship live fish, our preferred online retailers often carry rummy-nose tetras so check out their current selection. For more stocking suggestions, learn about the top 10 favorite tetras you have to try.