The fastest way to find a fish tank is to check big-box retailers first, then specialty aquarium shops, then online sellers

You can buy a fish tank at a big-box pet store like Petco or PetSmart, which stock tanks in multiple sizes and are usually within a short drive. You can also visit aquarium specialty shops in your area, which typically carry higher-quality equipment and staff who know tanks well. If you want to compare prices or need a specific size, online retailers like Amazon, Aqueon, and Marineland ship to your home, though shipping costs for large tanks can be steep. Local hardware stores sometimes carry small tanks and supplies. The choice depends on whether you need the tank today, want informed information, or are willing to wait for delivery to save money.

Key Takeaways

  • Big-box pet stores like Petco and PetSmart have tanks in stock and let you see the size in person before buying.
  • Specialty aquarium shops usually have more tank styles and experienced staff who can answer setup questions.
  • Online retailers offer wider selection and sometimes lower prices, but shipping a large tank can cost $30 to $100 or more.
  • Check store websites or call ahead to confirm the tank size you want is in stock before making the trip.
  • Buying locally means you can set up the tank the same day; buying online means waiting several days for delivery.

Big-Box Pet Store Chains

Petco and PetSmart are the most common chains and have locations in most cities. Both carry a range of starter kits and individual tanks, usually in 10-gallon, 20-gallon, and 40-gallon sizes. You can walk in, see the tanks in person, and take one home the same day. Staff knowledge varies—some employees know tanks well, others do not—so bring a list of questions about filtration and lighting if you need help.

Prices at big-box stores are usually higher than specialty shops or online, but you pay for convenience. Check the store's website or call the location nearest you to confirm they have the size you want in stock. Many stores let you reserve items online and pick them up within a few hours.

Specialty Aquarium Shops

Local aquarium shops carry a wider selection of tank styles, sizes, and brands than chain stores. Staff at these shops typically have hands-on experience and can advise you on filtration, lighting, and setup—especially useful if you are new to keeping fish. They often stock higher-end tanks and equipment alongside budget options.

To find a specialty shop near you, search "aquarium store near me" or check Google Maps. Prices are sometimes lower than big-box stores because they buy in bulk and have lower overhead. Call ahead to confirm they have the tank size and type you want, since smaller shops may not stock every size every day.

Online Retailers and Shipping Costs

Amazon, Aqueon, Marineland, and Chewy all ship fish tanks to your home. Online shopping lets you compare prices across sellers and read customer reviews. You can also find specialty tanks—like corner tanks or tall tanks—that may not be stocked locally.

The catch is shipping. A 20-gallon tank costs $15 to $40 to ship, and a 55-gallon tank can cost $80 to $150 because of weight and size. Some retailers offer free shipping on orders over a certain amount, so buying a complete kit (tank, filter, heater, light) together can reduce the per-item cost. Delivery usually takes 5 to 10 business days. Check the return policy before ordering—tanks sometimes arrive cracked, and you want to know how to send it back.

Walmart and Hardware Stores

Walmart carries small tanks (usually 10 to 20 gallons) in the pet section, and prices are competitive. Stock varies by location, so check online or call ahead. Home Depot and Lowe's sometimes stock small tanks and aquarium supplies in their garden sections, though selection is limited and staff may not know much about fish tanks.

These stores are worth checking if you are already shopping there or if you need a tank quickly and your local pet stores are out of stock. Expect fewer size options and less informed information than specialty shops.

Used Tanks and Secondhand Options

Facebook Marketplace, Craigslist, and Nextdoor often have used tanks for sale locally. Buying used can save 30 to 50 percent, and you can pick it up the same day. Before buying, inspect the tank for cracks, leaks, and scratches. Ask the seller how long they used it and why they are selling. A tank that sat unused for years may have mineral buildup inside that requires cleaning.

Used tanks come without warranties, so test it with water before adding fish. Fill it in your bathtub or outside, let it sit for an hour, and check for leaks. If it holds water, you have a working tank. If it leaks, you have saved yourself from a flooded floor.

What to Check Before You Buy

Write down the tank size you need before you shop. Tanks are measured in gallons, and the difference between a 10-gallon and a 20-gallon is significant—a 20-gallon is roughly twice as long and wide. Measure the space where you plan to put the tank and bring those measurements with you or check them against the product listing online.

Look at what comes in the box. A starter kit includes the tank, a filter, and sometimes a heater and light. Buying a kit is usually cheaper than buying each piece separately. Check whether the filter is rated for the tank size—a filter rated for 10 gallons will not clean a 20-gallon tank well. Read the product description or ask staff whether the kit includes a heater; many do not, and you may need to buy one separately.

Frequently Asked Questions

Can I buy a fish tank and set it up the same day?

Yes, if you buy from a local store. You can take the tank home, fill it, and add the filter and heater. However, you should let the water sit for 24 hours and run the filter before adding fish, so the water temperature stabilizes and beneficial bacteria begin to grow. Rushing this step can harm the fish.

What is the difference between a kit and buying a tank separately?

A kit bundles the tank, filter, and sometimes a heater and light into one package at a lower total price. Buying separately lets you choose each piece, which is useful if you want a specific filter or light. Kits are better for beginners because everything is designed to work together.

Is it cheaper to buy online or in a store?

Online is often cheaper per item, but shipping a large tank can erase the savings. A 20-gallon tank might cost $5 less online but $25 more to ship. For small tanks under 10 gallons, online is usually cheaper overall. For large tanks, compare the total price including shipping before ordering.

What size tank should I buy?

A 20-gallon tank is a good starting size for most fish and is easier to maintain than a 10-gallon. Smaller tanks require more frequent water changes and are harder to keep stable. Larger tanks (40 gallons and up) are more forgiving but take up more space and cost more. Start with what fits your space and budget.

Should I buy a used tank?

Used tanks are cheaper and often in good condition. Always inspect for cracks and test it with water before buying. Avoid tanks with visible damage or cloudiness inside that will not rinse clean. If the price is significantly lower than new, ask why—the seller may know something about a leak or defect.