Aquarium keeping in the USA

Units: US gallons

In the US, tank sizes and dosing are in US gallons (1 US gallon ≈ 3.78 L). When you use stocking rules, heater wattage, or filter flow, stick to US gallons so labels and charts match. Most US products (API, Seachem, Aqueon) are labelled in US gallons.

Tap water by region

Water hardness and pH vary a lot. The East and Midwest often have hard, alkaline tap; the Pacific Northwest and parts of the South can be softer. Always use a dechlorinator and test your tap so you can pick fish that suit your water parameters. Well water is common in rural areas — test for nitrate and metals.

Retail and brands

National chains like Petco and Petsmart stock tanks, filters, and fish; local fish stores (LFS) often have better advice and rarer species. Common US brands include API (test kits, conditioners), Seachem, Aqueon, and Tetra. Use App-aquatic to log tests and reminders no matter where you shop.

Lacey Act and invasive species

Federal and state laws restrict certain species to protect native wildlife. The Lacey Act bans transport of listed invasive fish and plants across state lines. Some states ban or restrict species like snakehead, carp, or certain cichlids. Never release aquarium fish or plants into the wild; check your state’s rules before buying.

Quick takeaways

• Use US gallons for dosing and stocking; US products are labelled accordingly.
• Test your tap — hardness and pH vary by region; match fish to your water.
• Support local fish stores when you can; national chains are convenient for basics.
• Obey Lacey Act and state rules; never release fish or plants into the wild.