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Argyropelecus Hemigymnus Care Guide



argyropelecus hemigymnus Introduction


For the aquarium hobbyist, it is pretty much fair to always explore most of the beautiful things to complete the aquascape.


Whether you have just started or been a while in doing this, it is great to see the coloration of your lovely pets moving around in their dwelling. For all aquarists, it is an irreplaceable moment in their life.


You can always add something new to your aquarium. And if you want to add something to your 15 gallons of the tank, the argyropelecus hemigymnus can make a great choice for you.

The argyropelecus hemigymnus  has such a bizarre shape of the body and intriguing coloration which is often sought by hobbyists. The hatchetfish came from the meaning of “compressed body”. The fish shape is also almost similar to the head of the hatchet.



Category Rating
Level of care Difficult
Temperament Peaceful
Appearance Silver
Life expectancy 2-5 years
Size 1.25 inches (3.2 cm) to 2.5 inches (6.5 cm)
Diet Carnivore
Family Gasteropelecidae
Tank size 15 gallons
Tank environment Freshwater with floating plants and rocks
Tank Mates Other small fish


About argyropelecus hemigymnus



The hatchetfish is found in the Guianas of northern South America in marshes, flooded areas, brooks, ditches, and rivers. It is found in the Amazon’s middle and lower rainforest streams.


Hatchetfish live just below the surface of the water, among marsh and water plants, and raised roots. They shoal together to hunt larval insects and other aquatic invertebrates. Hatchetfish can fly away from danger in an instant as a larger fish comes to prey on them.


The argyropelecus hemigymnus got its name from its unique shape and appearance. The bottom rounded triangle really resembles a hatchet. The disproportion of the body might seem awkward for some people. But for avid enthusiasts, it is something

beautiful and mesmerizing.


The silver sheen with the brownish to golden yellow colors is the basic coloration of this little pet.


There are numerous hatchetfish species accessible in the hobby, and they are often offered under incorrect names. The common hatchetfish (Gasteropelecus stencil) is commonly advertised as the silver hatchetfish, despite being bigger and less timid.


Silver hatchetfish grow to little about 1 1/4 inches in the home tank (3.5 centimeters). but the half-naked ones can reach up to 6.5 cm in captivity. Their life expectancy can reach five years.


argyropelecus hemigymnus Tank Requirements & SetUp / Tank Guides


The blackwater environment is the original habitat of the particular fish. The best way to make them thrive and live for a longer time is by replicating their real habitat as maximally as possible.


The blackwater environment’s characteristics can come with the live plants, outcroppings, branches, and some dropped leaves. Of course, you need to provide enough space for the fish to swim and explore their dwelling area.

Adding this fish to bare tank will make the fish anxious. They won’t survive in that condition. So, make sure you prepare everything before adding your little buddies there.


Hatchetfish are a popular aquarium inclusion, although they are forest residents. If you have a big aquarium, consider dimming or muted LED lights. As a way to replicate their native environment, choose plants that grow along the water’s edge. Pour représenter a riverbed, choose a dark substrate.


Unusual as it may seem, it has happened that fish purchased from local shops have attempted to fly. A hatchetfish tank must be completely contained to avoid unexpected flight. Since the fish size is small, you won’t want to take a huge risk by letting even a small slit take place.

The pH should be at 7.6 to 7.8. They can live with lower pH but I wouldn’t recommend it if you want to make them live longer.


The temperature of the water should be around 75 to 80° F. They can still tolerate colder or warmer temperatures. But they cannot withstand too extreme changes of the temperature.


The tricky part about half-naked hatchetfish is that they are hard to feed when they are in the giant group. The wholesalers usually feed them with less nutritious foods before dispatching the specimens to the local shops.


In the local shops, sellers won’t be able to pay attention to every single specimen. It is not that they are lazy or whatsoever. They have plenty of specimens to watch over. Therefore, the rest of the things will be on you. Carefully pick the buddies that you want to add to your aquarium.


It is imperative to understand that they might be possibly ill or have a lower immune system. so, when you bring them home, I suggest you keep them in a separate tank to feed them well. Make sure they are healthy and well first before adding to the main community tank.


If they manage to get into your aquarium with wellness, they will be in good health and will be able to live happily ever after. A minimum of a 20 gallon tank is required for the smaller Hatchetfish, but a larger tank is almost likely required for the larger ones.


Get a number of them (6-12), they will be great in the group. Keep an eye on them while they eat and grab the excellent ones because buying a batch of them is a bit pricey.


Beware with the half-naked buddies since they are good jumpers!. This behavior cannot be expected in a home aquarium, though.


In order to prevent unapproved leaps, a tight-fitting lid is essential! If your aquarium does not come with this feature, you must quickly make one to prevent the escapes from happening.


 The hatchets can target leap through big holes or filter access cut-aways in the lid.


Hatchetfish are all excellent swimmers who may live their whole lives just millimeters below the surface. For example, several species feed, sleep and even reproduce just below the surface. It is a bizarre thing, indeed. But it is always fun to see them enjoying their life in your prosperous tank.


While the Gasteropelecus family has several species, only a few are commonly seen in the pet trade. It is also known as the silver hatchet, the black-winged hatchet, and the common hatchet.


This quartet of big-bellied communal tropicals has a lot to offer, and each one is distinct enough from the others to be appealing.


The decoration of the half-naked hatchet is easy. You can literally get the items in any pet stores that you can find in your area. The floating vegetation is optional. But you can consider adding it, recalling that this species tends to be active just below the surface.


They will use the floating plants to hide, sleep, mate, scout, or any other purpose. You could consider adding water lettuce for the floating one.


Grass-like plants and the tall ones can be great options too. But make sure that these plants can grow to reach the top of your aquarium. It will provide a lot of benefits for your hatchet buddies.


They seem to find happiness and security whenever they use the floating plants and other objects in the mid to top dwelling areas. If you add the vertical leaves, it will be fun to see them darting through these.


argyropelecus hemigymnus Tank Mates


You won’t put a single argyropelecus hemigymnus in the aquarium. It will die on the first day. These little friends are naturally schooling fish. That means you can keep them in the group of 10 or more, depending on the size of your aquarium. With such a great aquascape, they can be friends with anyone in the community tank.


They won’t harass other fish and tend to dodge to avoid any problem. There is no harm coming from this peaceful creature. They are also friendly to the bottom dwellers. So, make sure you add the peaceful bottom dwellers as well.


They can live together with the peaceful fish species that have the same size as them. Do not put larger fish, especially carnivorous ones. You know, the hatchet can look so delicious to eat.


argyropelecus hemigymnus Diets/Food/Feeding


The half-naked hatchet is a carnivore. The little pets love to devour larva and insects that are located nearby them. The aquatic invertebrates and zooplankton near the water surface can also be their delicious meals.


The good thing about keeping these fish in your aquarium is that they are effective mosquito killers. They can keep the numbers of these annoying insects down.

You could also add the dried foods to their diets. Live and frozen meaty foods are also preferable such as grindal worm, daphnia, and artemia.


You can also raise other small insects in bulk to save more money to feed your buddies in bulk. With such proteins, they can thrive.


But one more thing you need to do to keep them happy. The insects and live foods are their bio-loading. So,before you give them to your fish, you should add fish flakes first. These items will make your fish’ stomach fuller.



argyropelecus hemigymnus Breeding guideline




No external sexual traits. These bigger, fuller-bodied individuals are presumably mature females. Color lines have somewhat diverse strains owing to inbreeding and observation techniques. When not in breeding form or not closely observed, all hatchetfish appear silver.


This species’ spawning is rare. This is a tough fish to produce, and only a skilled breeder or someone who likes a challenge should attempt it. Breeding the half-naked argyropelecus hemigymnus  is definitely not for beginners.


To lay eggs in a tank illuminated by natural sunlight, this species spreads them among the high roots of plants near the water’s surface. Simulated moonlight can also spawn. 86F simulates late spring/early summer in their native environment.


The males will do the dance to attract the females to spawn.


The sticky eggs cling to the tiny leaves. Here is what the vertical leaves used for.


The fry, which hatch in 24-30 hours, is easy to raise.


See, the hard part is to replicate the nice conditions for the couples to mate.  


The argyropelecus hemigymnus do not consume eggs, therefore timing is less important than with other tropical fish. But after that hatching, there is another challenge to overcome.


The parents have the huge potential to eat their fry within 24 hours. So, you might want to take the parents out of the main tank.


Consider separating everything that loves to eat the fry. If you have snails in your aquarium, you will want to ban them first since they love to eat fish eggs.