Black Piranha Aquarium Care, Feeding and Native Habitat Information
The Black Piranha (Serrasalmus rhombeus) is truly impressive predatory fish specimen, with its large powerful body and many sharp teeth. For many hobbyists looking to keep a species aquarium containing aggressive predatory fish, the Black Piranha is the ideal fish. Black Piranha grow upwards of 17 inches in length and have powerful muscular bodies to match their impressive length and of course plenty of sharp teeth. Juvenile Black Piranha have a more silver body, darker spots on their sides and bright red eyes. As they grow into adults they lose their spots and develop a dark overall body coloration ranging between dark grey and black. With age and size typically comes aggression, with adult Black Piranha often being too aggressive to keep in anything but a large aquarium in a conspecific group. However, for hobbyists looking for seriously aggressive fish the Black Piranha is the ideal specimen.
Black Piranha originate from larger and deeper rivers of the northern Amazon, where they are accustomed to very clean and highly oxygenated water. They require aquarium environments that have excellent water quality, plenty of dissolved oxygen and internal water flow. Quality water conditions combined with a proper diet is essential to maintain the proper long term health of the fish. Suitable filtration systems for Black Piranha aquariums include high-end canister filtration and wet/dry sump based filtration. Strong water flow via a spray bar or additional power heads is also recommended to insure that there is adequate dissolved oxygen in the water. Being a messy eater that also requires pristine water conditions means that even hobbyists who have aquarium setups with excellent filtration will need to perform partial water changes to avoid the build up of nitrates and other dissolved solids. Properly sized aquariums with quality canister or wet/dry systems will generally require weekly 25% partial water changes in order to maintain the highest water quality.
While intolerant of poor water conditions, the Black Piranha is actually accepting of a fairly wide range of water pH and temperature as long as the changes are not sudden. Due to their size and sharp teeth, it is recommended that aquarium equipment like heaters and equipment wires be located outside of the aquarium or neatly tied off in the corner of the aquarium to avoid the Piranha from chewing on them. It is also important to cover the aquarium in order to prevent jumping and accidental contact between the Black Piranha and peoples fingers and hands. It is recommended that hobbyists design the aquarium after their natural habitat, which includes: sandy substrate, driftwood or root, aquatic plants and smooth rocks or rock piles. While this type of setup is not specifically required, it is essential the Black Piranha have some aquarium decor to provide them places to hide. Bare tanks or tanks with minimal decor and bright lighting will stress the fish and can cause illness or shorten their life span.
In terms of suitable tank mates for the Black Piranha the list is rather short. Black Piranha should essentially be kept in species only aquariums, with the few exceptions being possibly armored catfish or larger plecos. Even conspecific groups can be problematic in smaller aquariums as Black Piranha will often fight amongst themselves when the aquarium or water conditions are not suitable. In addition to excellent water conditions Black Piranha require ample space within the aquarium or they will become very aggressive towards all other tank mates including other conspecifics. A single specimen can live comfortably in a 75 gallon aquarium, with groups of Piranha requiring larger tanks of 150 gallons or more.
Wild Black Piranha consume a wide variety of available foods ranging from the fins of other fish to decaying carcases and even seeds and fruits that have fallen from the jungle canopy. The bulk of their diet consists of smaller fishes, crustaceans and insects. However, as an opportunistic feeder the Black Piranha will scavenge decaying meaty items like dead animal, bird or larger fish carcases that it comes across. Hobbyists should feed meaty foods that are present in the fishes natural diet like fish flesh, crustacean flesh, insects, worms and other similar items. Feeding mammal meat like chicken, beef, etc. is not recommended because the Black Piranha have difficulty fully digesting these types of food and will over time build fatty deposits of undigested fats. Feeder fish like goldfish are also not recommended for a daily staple diet because they are high in fat and offer little nutrition for the Black Piranha. Young Black Piranha will do best with bloodworms, tubifex worms, chopped crustacean flesh (prawns, cockles, shrimp), chopped whitefish or earthworms. Adult Black Piranha should be fed the same types of items only in larger pieces and larger quantities. Feeder fish, chicken livers, beef hearts, etc. are suitable for occasional feedings, but should not make up a significant portion of the fishes diet.