Buy a tank that corresponds with the number of piranhas you’ll have. For example, if only want two animals, a 40 gallon tank should be enough space for them. As a rule of thumb, you want about 20 gallons of water per animal or 60 gallons for 4 piranhas. [5] X Research source Make sure to the biggest tank you can afford so that your piranhas can flourish. If you’re trying to save money, consider a second hand tank. Wash any tanks before introducing your piranhas to them. Consider getting an optional tank screen for the top. Piranhas can jump and injure their owners if they’re hungry. You also want to ensure that pets or small children don’t fall in the tank.
Put the tank in a place with a relatively consistent temperature of 75 to 80 degrees Fahrenheit (21 to 25 Celsius). Attach a thermometer to the aquarium to monitor the temperature. You shouldn’t put the tank anywhere it may get direct sunlight or be exposed to radiators or heating devices. Find a low-traffic space in which to put the tank. If there are too many people walking by the tank, it can stress out piranhas and may make them aggressive. Consider putting the tank in a space with low light. In the wild, piranhas live in murky water that is under the canopy of the rain forest so their eyes have adapted to dimmer lighting.
Add several small filters to the water or one very powerful external filter to keep the water clean. [9] X Research source Consider getting a heater for the water to keep the water a consistent temperature. [10] X Research source
Decorate the tank with live and plastic plants as well as smooth gravel, and pieces of wood. Be aware that Piranhas may destroy live plants. A clean piece of PVC piping can also provide piranhas a place to hide if they feel stressed. [13] X Research source Choose decorations that you like. You can use live or plastic plants or a combination. If you’re using live plants, consider hardy, low-light options such as hornwort, java moss, or fern. Any type of plastic plant you like will work. Soak any wood or driftwood in a tub or bin until it turns a brownish color. Many piranhas like the dark color of the water, but it may be difficult to see your fish. Make sure the driftwood fits in the tank and gives your piranhas plenty of space to swim freely. Use smooth rocks and gravel that only barely cover the bottom of the aquarium. You can safely use granite, basalt, gneiss, slate, and quartz. Avoid limestone, marble, dolomite, calcareous sandstones, chalky rocks as well as corals and sea shells. All of these can upset the pH of the tank. Place as many decorations as you like in the tank, but remember that your piranhas should be able to swim freely without hindrance. A good rule of thumb is 50-75% coverage in the tank to make your piranhas feel comfortable. [14] X Research source Too many decorations can also more quickly decrease the water quality.
Write a schedule for yourself to clean the water at the same time each week so that you don’t forget. Clean the aquarium more often if you notice excess waste—remember piranhas are messy—or odor. [17] X Expert Source Doug LudemannAquarium Care Professional Expert Interview. 27 August 2019. Be aware that you shouldn’t remove your piranhas from the tank if at all possible. Remember that piranhas generally attack when they feel threatened or are hungry. Protect your hands with a pair of heavy gloves when cleaning. If you absolutely have to remove your piranha from the water, place a bucket or large fish net in the tank and quickly place your piranha in a separate tank. Use a water changing device, or python, from a local pet store for best results. [18] X Expert Source Doug LudemannAquarium Care Professional Expert Interview. 27 August 2019. These hook up to a sink and make it easy to clean the tank. This can also minimize the risk of your piranha becoming aggressive with you. [19] X Research source If you don’t have a water changing device, gently remove each piranha and put them in a separate holding tank while you clean. This will allow you to clean the tank without stressing your fish or getting injured because the piranhas are stressed. Vacuum the gravel and remove any waste while using the water changing device or when the tank water is low and no piranhas are in the tank.
Test tank water with a test kit that you can get at large retailers and pet stores. Test to figure out potential problems like low oxygen, high ammonia, and acidity. [21] X Research source Fix any problems with the water. The pH level can range from 5. 5-8. 0. Use a chemical neutralizer to restore the pH levels if they are off. Oxygen saturation should exceed 70%. If it doesn’t, you may need to replace your filter or filters. [22] X Expert Source Doug LudemannAquarium Care Professional Expert Interview. 27 August 2019. Use a thermometer to make sure the temperature is between 75 and 80 degrees Fahrenheit. If necessary, turn up the heater until you reach the optimal temperature range.
Smell the water to see if it has a foul odor. This is a good sign you need to change the filters.
Feed your piranhas once a day. Feeding them more often can lead to overfeeding and increases the amount of waste in the tank. Good live foods are guppies and minnows. Piranhas will not usually eat characins as they are a characin themselves. Piranhas should eat everything given to them within two minutes or this can contribute to poor water quality and susceptible to disease. The only exception is vegetables, which can be left for a few hours. Give your piranhas processed, frozen, and freeze dried foods including fish, crabs, prawns, rainworms and shed snakeskin. Occasionally feed them green vegetables such as raw zucchini, spinach, or potato. Avoid giving piranhas dry market feed, flakes or granules. [25] X Research source Avoid feeding piranhas live animals. Not only can they introduce disease to your piranhas, but can contribute significantly to waste in the tank. [26] X Research source
Lethargy or sluggishness Unwillingness to eat Severe body damage such as bites or chunks of missing flesh Cloudy or missing eyes Labored breathing Visible parasites on the skin[27] X Research source
Aiming towards gravel and tilting the tail, both of which are signs of aggression to keep someone from entering the piranhas space Growing paler in appearance, which can be due to the colors not coming out yet or as a sign of stress Turning on their sides and rubbing the gravel to itch themselves, which can indicate poor water quality, infection, or just needing to scratch Holding their mouths open and wagging violently from side to side, which is a sign of the piranha being ready to fight Chomping mouths repeatedly, which is a sign of hunger Circling the tank repeatedly as a sign of displeasure with something in the tank or controlling the territory Intensify colors, which are a sign of the piranha being very happy or angry Turning black, which is a sign that a piranha is ready to breed Getting side by side and wagging tails, which is a sign that piranhas are breeding or ready to fight Biting each others’ fins as a warning to desist or be killed
