Black Ruby Barb (Pethia nigrofasciata): Ultimate Care Guide

Finding the right choice of fish for some tanks can be a tall order. Sometimes they are too aggressive or don’t mesh well with the fish you already have in your tank. Others may be too meek or small. If you’re looking for a small, peaceful, and gorgeous companion, look no further than the Black Ruby Barb. This fish is known for their beautiful colors, as well as its gentle nature. The Black Ruby Barb could be the perfect addition to your tank and family. Continue reading for all the information you’ll need about owning and caring for this elegant, friendly, unique little fish.

The Black Ruby Barb, also known as the Ruby Barb, Black Barb, and the Purple-Headed Barb, is a species of barbs native to Sri Lanka, off the Indian Coast. These little fish are known for their dark red or purple hue when they are fully grown. Black Ruby Barbs used to be extremely abundant in forest streams and river basins in Sri Lanka. However, the number of Black Ruby Barbs has catastrophically dwindled over the years. The cause of this steep decline in the population is due to over-catching by those intending to sell them into the aquarium hobby. Rapid Deforestation is another major cause of the decline of the Black Ruby Barb. The native habitats of these little fish have been mostly destroyed. It was so bad that Black Ruby Barbs were on the brink of extinction at one point. However, now they are classified by the International Union for Conservation of Nature as vulnerable. The sale of Black Ruby Barbs caught in Sri Lanka is strictly prohibited, meaning that all the Black Ruby Barbs for sale in the aquarium hobby have been commercially bred. This breeding process has created new variants of Black Ruby Barbs with new colors and differences in their fins.

Care is essential for any pet you choose to add to your family, especially the aquatic one. Many people outside the aquarium hobby do not realize how difficult it can sometimes be to care for fish. They naively believe that all you need is a tank, some water, and fish. Learning just how difficult some fish are is a right of passage for any aquarist or hobbyist. Black Ruby Barbs require precise care and preparation. If you’re up for the task, then let’s get started.

Black Ruby Barb
Black Ruby Barb (Pethia nigrofasciata)

Black Ruby Barb Care

Caring for a Black Ruby Barb isn’t too tricky. These fish are small, so ensure your tank doesn’t have too many large fish. The pH and temperature requirements are very standard compared to some other fish. Black Ruby Barbs are also very peaceful, meaning they likely won’t fight for dominance in your tank. They are also an omnivorous species, so feeding them shouldn’t be an issue. With just a bit of research, you can be sure your Black Ruby Barb is healthy, happy, and thriving in your tank. The upcoming sections will have more information on the temperature, pH, tank, and feeding requirements for the Black Ruby Barb.


Black Ruby Barbs prefer slightly cooler temperatures than other species of fish. This reduces the potential amount of tank mates that you can comfortably keep with your Black Ruby Barb. Black Ruby Barbs prefer their habitat to stay between 72 to 79 degrees Fahrenheit or 22 to 26 degrees Celsius. You will definitely need a heater to help maintain your tank and ensure it stays within the required parameters. These fish tend to stay towards the bottom of the tank, which is usually cooler than other locations in the tank. This is because of plants and other vegetation diffusing any lighting and helping keep the water cool.

Water pH

Most fish are very susceptible to any change in their water conditions; Black Ruby Barbs are no exception to that. The pH level of any tank is critical, and this is because any slight changes in the pH could cause the species in the tank to get ill. When setting up a tank for Black Ruby Barbs, the pH level should be between 6.0 to 6.5. Frequent checks will ensure that you can catch any issues and make the necessary changes before your fish are impacted. Vigilance is the key to owning any pet. You need to ensure to give fish the same level of care you would give to a dog or any other pet. It would be best if you never neglected them.

Black Ruby Barb Size

The size of a species when fully grown is something that is surprisingly overlooked by many aquarists. Some species start out small and can reach a few feet in length when fully grown. Thankfully, Black Ruby Barbs are not one of these species of fish. The Black Ruby Barb is usually only around 2 to 2.5 inches when fully grown. This smaller size makes it the perfect choice, not only for smaller tanks but for community tanks as well. Black Ruby Barbs are the ideal size for people with little room for a large tank, such as those in dorm rooms or apartments.

Black Ruby Barb (Pethia nigrofasciata)
Black Ruby Barb (Pethia nigrofasciata)

Food and Diet

Black Ruby Barbs usually like to stay near the bottom of their tank, which is perfect because these small fish are bottom feeders. In the wild, Black Ruby Barbs will scrounge around the bottom of the habitat looking for organic material in the detritus. Detritus and algae make up most of the diet of the Black Ruby Barb. Despite being omnivores, you want to ensure that your Black Ruby Barb’s diet mainly consists of plant matter. Flakes are a good option, but other options exist for those who don’t like to feed their pets overly processed foods. Some great choices of fresh foods are shelled peas, lettuce, spinach, or raw zucchini. Black Ruby Barbs also appreciate the occasional live food. You should treat with live bloodworms or brine shrimp every week or two.

Black Ruby Barb Lifespan

The lifespan of any pet depends on the care you give them. When it comes to any pet’s expected lifespan, there aren’t any guarantees. You must make sure their habitat is to their liking, avoid any undue stress, and most importantly, you need to provide them with a healthy and balanced diet. A fish’s expected lifespan is genuinely just a shot in the dark. If you don’t carefully maintain their water and tank parameters, their expected lifespan will drop. On average, the life span of a Black Ruby Barb is around five years. That number will quickly fall if you neglect your Black Ruby Barb.

Black Ruby Barb Tank Size

When it comes to choosing a tank for any fish, the size is extremely important. You need to ensure that your tank is large enough not only for the fish in your tank but for any necessary vegetation or decorations. When selecting a tank for your Black Ruby Barb, you need a tank that is at least 30 gallons in volume. A 30-gallon tank is small enough to make Black Ruby Barbs an excellent choice for those in apartments or even dorms. You will need to get an ever larger tank if you plan to include more Black Ruby Barbs and likely even larger if you plan on adding them to a community tank.

Black Ruby Barb Tank Setup

If you’re committed to having a Black Ruby Barb, you need to ensure that you set up your tank to their liking. Temperature and pH levels are critical to any tank setup. When setting up a tank for a Black Ruby Barb, you want to keep the temperature between 72 and 79 degrees Fahrenheit. The pH level of a Black Ruby Barb tank should be within the range of 6.0 to 6.5. As for substrate, you’ll want a darker sand or gravel substrate. Black Ruby Barbs are used to a darker habitat, so you’ll want to use floating leaves to diffuse any lighting. Black Ruby Barbs love to hide, so you’ll need to provide them with many hiding spots. You can create hiding spots for your Black Ruby Barbs with caves or live vegetation. Be sure not to provide too many features in your tank because Black Ruby Barbs like to swim, so you want to give them plenty of room to do that.

Black Ruby Barb Breeding

When breeding Black Ruby Barbs, the first and most necessary step is identifying a male and a female. Male Ruby Barbs tend to be slightly larger than their female counterparts. They also have entirely black dorsal fins, while only the base of the female’s dorsal fin is black. Female Black Ruby Barbs have pale anal and pelvic fins, while the male Black Ruby Barb has black anal and pelvic fins.

Black Ruby Barbs are an egg-scattering species, and they tend to mate in pairs. Unfortunately, Black Ruby Barbs will not hesitate to eat their own eggs and must be removed from the tank once they have laid and fertilized their eggs.

If you plan on breeding Black Ruby Barbs, you need to prepare a secondary breeding tank. The water in the breeding tank needs to be between 77 to 82 degrees Fahrenheit and soft and acidic. Including some vegetation with leaves such as Java moss is also crucial. This is important because it gives the Black Ruby Barbs a location to scatter their eggs on. It is also recommended to keep the lighting dim.

During the breeding season, the male Black Ruby Barb will begin to change colors into a darker ruby color. The female Black Ruby Barb will not change colors but will instead start to get more plump and round as she fills with eggs. It is essential to continue feeding your Black Ruby Barbs their regular diet during this time, but you want to add some additional live food.

The breeding process will begin once the Male courts the female. Male Black Ruby Barbs court their female counterparts by spreading their fins and swimming around them. Once this has started, the female will begin to lay her eggs. Once she has finished laying her eggs, you must remove both of them from the tank.

After removing the parents from the tank, you must remove any light sources. This is because Black Ruby Barb fry are extremely sensitive to light. Twenty-four hours after the eggs are laid, they will likely begin to hatch. Newly hatched fry can be fed commercial fry food. After a few days, you can start to feed the fry young brine shrimp.

If the Black Ruby Barbs eggs do not hatch, that is likely because the parents did not have a balanced diet. If you wish to try breeding again, you need to feed the spawning pair higher-quality food.

Black Ruby Barb Disease

Diseases are usually very avoidable in a tank setting. The easiest way to avoid any disease, illness, or infection is to monitor the water conditions in your tank carefully. If carefully observed, you catch any changes in water quality or pH balance. Even with careful monitoring, you’ll still want to perform routine water changes to help clear any debris or waste. Unfortunately, your species can still become infected even with a watchful eye. Ich is one of the most common diseases that can affect freshwater fish, and Black Ruby Barbs are no exception to that. Ich is easily treatable if caught early enough. You can diagnose Ich by the appearance of white spots or splotches on your fish’s body. You can get medicine to treat Ich at a vet or aquarium store, but ensure the treatment is safe for all species in your tank.

Where can I find Black Ruby Barbs for sale?

Black Ruby Barbs are small and popular enough that most aquarium hobby stores likely have them in stock. They can also be purchased in many different locations online. On average, the Black Ruby Barbs sell for around $12, making them an affordable choice for anyone. When purchasing online, ensure that the dealer is respected and careful.