Piranha are banned in 38+ US states under invasive species laws. Fast Aquatics's checkout filter blocks piranha shipments to any of those states. Legal piranha purchases require checking your state's aquatic species list AND buying from a vendor licensed to ship within your state.
Piranha (genus Pygocentrus and Serrasalmus) are one of the most heavily regulated freshwater fish in the United States. The regulation isn't federal - each state has its own list of prohibited species - but the practical effect is that piranha are illegal to keep in most of the country.
Alabama, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Utah, Vermont, Washington, West Virginia, Wisconsin, Wyoming.
That's 46 states + DC where piranha is either fully prohibited or requires a permit that hobbyists can't realistically obtain. Texas explicitly does NOT ban red-bellied piranha but bans other species. Indiana, Mississippi, and a few others have gray-area enforcement.
Even where piranha is legal at the buyer's end, shipping piranha across state lines triggers the federal Lacey Act - a law that makes it a federal crime to transport an animal in violation of any state law. This applies to the seller, the carrier, AND the buyer. Fast Aquatics's state-restriction database (52 rules across 50 states) blocks piranha at checkout when the buyer's shipping address is in a banned state, both to protect the buyer and to protect the marketplace from Lacey Act exposure.
You can buy piranha where it's legal, but you cannot transport it across a state line into a state where it's banned. Even moving with an existing pet piranha across the wrong state line is technically a Lacey Act violation.
The state's Department of Agriculture or Fish & Wildlife typically seizes the package, euthanizes the fish, fines the seller, and may fine the buyer. Fast Aquatics's state-filter is designed to never let this scenario happen on our platform.
Whatever specific topic brought you here, four fundamentals govern long-term aquarium success: water quality, parameter stability, biological filtration, and species-appropriate husbandry. Skip any one and the others struggle to compensate.
Water quality: ammonia + nitrite at zero, nitrate under 30 ppm freshwater + 10 ppm reef. Test weekly with API or Salifert kits. Use our water parameter checker to score your readings against your tank type.
Parameter stability: stable wrong parameters beat fluctuating ideal parameters. Most fish tolerate a wide pH range if it's stable. Sudden swings of 0.4+ pH or 5+°F kill fish faster than chronic suboptimal values. Use temperature controllers (Inkbird) + automated dosing for consistency.
Biological filtration: the bacterial colony on your filter media + rock + substrate is the engine. Never replace all media at once. Use our filter turnover calculator to size correctly.
Species-appropriate husbandry: research adult size, territoriality, diet, and tankmate compatibility before purchase. Use our tank stocking calculator + compatibility guides.
How long does an aquarium take to set up? 4-6 weeks for full cycling + first stocking. Use our cycle ETA calculator + how long does cycling take.
What's the best aquarium for beginners? 20-gallon long. Big enough for parameter stability, small enough for budget + space. See beginner picks.
How often should I do water changes? 25-30% weekly. See water change frequency Q&A + water change calculator.
Why does my fish keep dying? 5 leading causes: uncycled tank, wrong species pairings, no quarantine, undersized tank, neglected water-change schedule. See full diagnosis.
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