Big Barb Bonanza!

Hypsibarbus vernayi is a fish that is common in the Mekong delta, regarded primarily as a food fish and generally sold locally and freshly caught. They are also frequently seen in Local Aquarium Stores, and they are a great fit for this, being a shoaling fish that is very easy to care for and feed. There are only two caveats to this and the first is that these fish need very oxygenated, flowing water; the second is that they are popular with people who love big fish and big tanks.

Common naming this fish gets confusing as there are actually two fish that are nearly identical (especially when young) and are frequently caught together and sold as one or the other species. You'll see Hypsibarbus wetmorei being sold as Hypsibarbus vernayi and vice versa and often sold in groups together! As a result, their common names also frequently overlap! H. vernayi is commonly called the Big Scale Diamond Barb in North America, but it is also commonly called Lemon Fin Barb, Golden Belly Barb and the fairly boring Lemon Barb.

The easy to spot difference between the two is that H. vernayi will take on a yellow cast on the lower half of its body, with yellow the pectoral, pelvic and anal fins (all the ones on the bottom), while H. wetmorei will develop red fins on all the same fins. These colors develop fairly young but can be faint. Luckily, if you have both of them, their requirements are nearly identical. If you're looking for the slightly smaller one, you're reading the right article, it's H. vernayi (yellow finned fishy).

In its native range, Thailand, Vietnam, Laos, Cambodia and southeast China, these fish have several names, most of which don't translate to English well, or translate to things that are very simplistic, like “Freshwater Fish.” They are most frequently found in medium sized tributaries to the Mekong River, always in flowing water with nominal cover. Hypsibarbus vernayi tends to disappear from waterways that get impounded. There is some conflicting data out there on whether or not the fish is migratory and that dams prevent their reproduction, but it is clear that they require very oxygenated water.

These fish are omnivores in the wild and spend most of their time in the middle and bottom of the water column. They'll eat just about any invertebrate that moves, and unsurprisingly some of their favorite foods are shrimp, worms and even snails! They will also eat any fish they can catch. There is some debate about the role that vegetation plays in their diet, but it is clear that they do better in captivity when offered some greens and that they will definitely consume soft plants. In house, we feed them a meaty mix of foods from Gamma, and they greedily accept mysis, bloodworms, mosquito larvae and chopped prawn. We also offer them both pellets and shots from Nutramar in the Freshwater Algae and Color Boost formula to get them their greens. They can be fed anywhere from one to three times per day and will usually not stop eating until the food is gone. They will grow faster with more food but will also produce copious waste. We suggest that if you're going to feed more than once a day, you should reduce the amount of food per serving.

The display for Big Scale Diamond Barbs will need to be large, as they are a fish that does best kept in groups and can get to be a foot long; though a much more common size is in the ten-inch range, a size they can attain within two years. You can keep them in mixed groups with other large barbs, but regardless of what you keep them with, they are going to require a tank that is a minimum of six feet long and two feet front to back in order to house the bare minimum four specimens (six plus would be better). Many people into keeping this size fish keep them in ponds. They also need a lot of oxygen, and so we recommend having a filter that will turn over the entire aquarium volume five to ten times per hour. If your display is on the low end of this, or you are planning on keeping them in a pond, they will need supplemental oxygenation.

The interior design element of your display should be sparse, and many aquarists do not use a substrate which can help with waste removal. If substrate is chosen, it should be pebbles or other smooth rounded material that is inert and won't move in the substantial flow provided. Rocks should also be rounded, and a riverine (like a river) display is perfect. There are many good choices of aquarium safe rock available to Aquatropic partner stores from Eco-scape, and their Monument Rock series would be very appropriate (except, perhaps the volcanic glass). You can see this series here: https://www.qualitymarine.com/ecoscape/monument-rock-series.

In regard to water quality, these fish do well in a variety of water types, exact hardness and pH levels are less important than oxygenation and cleanliness. We've found them happiest in pH that is stable anywhere from 6.2 to 7.8, and in temperatures from around 68 up to about 78. It is easier to maintain higher oxygenation at the lower end of this range, but if you want them to get big fast, they'll grow faster in slightly warmer water. They are very intolerant of drops in oxygen, and high nutrient levels will compound this, so big frequent water changes and strong filtration should be the baseline for keeping them.

This is a fish that is best suited for very large aquariums and the kinds of fish you find in them. They aren't territorial unless they are too confined and so the list of things you can keep them with is long. They are very active, boisterous fish, and so keeping them with shy fish, or plodding swimmers isn't recommended. Tank mates should also be large enough not to look like a snack.

If you're a person looking for big, different fish, a group of Big Scale Diamond Barbs has a lot going for it. They're gorgeous and hardy when given an appropriate environment and do well with a variety of other fish. Head to your LFS and ask them to get you a group of Hypsibarbus vernayi from Aquatropic today! (and if your tank is REALLY big, they could mix you in a few Hypsibarbus wetmorei that get four or five inches longer too!)