The cheapest places to buy aquariums are big-box retailers, online marketplaces, and local classified sites

You can find affordable aquariums at Walmart, Target, and Petco, where starter kits often cost $30 to $80. Online, Amazon and eBay frequently have lower prices than in-store, and you can compare dozens of options without leaving home. Local options like Facebook Marketplace, Craigslist, and Nextdoor often have used aquariums for $10 to $40—sometimes complete with filters and decorations. The trade-off is that online shipping can be expensive for glass tanks, and used equipment may need cleaning or repair.

The size and type of tank you want determines where you'll find the best deal. A 10-gallon glass tank costs less at Walmart than a specialty aquarium store, but a 55-gallon used tank from a local seller is often cheaper than buying new anywhere. Plastic or acrylic tanks ship more easily than glass, so online prices tend to be better for those. Timing matters too—prices drop after the holidays and during back-to-school sales in August.

Key Takeaways

  • Walmart and Target stock basic aquariums for $30 to $80, and prices are usually lower than specialty pet stores.
  • Facebook Marketplace and Craigslist often have used tanks for half the new price, though you should inspect them for cracks before buying.
  • Amazon and eBay let you compare prices across many sellers, but factor in shipping costs for glass tanks, which can add $20 to $50.
  • Petco and PetSmart run sales during holidays and summer, so waiting a few weeks can save 20 to 30 percent on starter kits.
  • Plastic and acrylic tanks ship cheaper than glass, making online purchases more economical for smaller tanks.

Big-box retailers: Walmart and Target

Walmart and Target carry basic aquariums year-round in their pet sections, usually in the $30 to $100 range depending on size. A 10-gallon starter kit with filter and heater typically costs $50 to $70. Both stores stock Aqueon and Tetra brands, which are reliable mid-range options. Prices are often lower than specialty pet stores because these retailers buy in bulk and don't have the overhead of a dedicated aquarium shop.

Check the store's website before you go—many Walmart and Target locations let you see which tanks are in stock nearby and sometimes offer online pickup or delivery. This saves you from driving to a store that doesn't have what you want. Both retailers also run sales during major holidays and back-to-school season, usually in August and around Black Friday, when you can save 15 to 25 percent.

Pet store chains: Petco and PetSmart

Petco and PetSmart sell aquariums at higher prices than Walmart or Target, but they run frequent sales and loyalty discounts. A 20-gallon tank that costs $80 at full price might drop to $60 during a sale. Both stores offer price-match guarantees, so if you find the same tank cheaper online, bring the listing and they will match it. This can save you shipping costs if the tank is heavy.

These chains also bundle tanks with filters, heaters, and lighting in starter kits, which can be cheaper than buying each piece separately. However, the individual items are often marked up more than at big-box stores. Sign up for their rewards programs—Petco's Pals and PetSmart's Treats Rewards—to get member-only discounts and email alerts when tanks go on sale.

Online marketplaces: Amazon and eBay

Amazon and eBay have hundreds of aquarium listings, and prices are often 10 to 20 percent lower than in-store. You can filter by size, brand, and price, and read reviews from people who bought the same tank. Shipping is the catch: a 40-gallon glass tank can cost $30 to $60 to ship, which wipes out the savings. Smaller tanks under 20 gallons ship more cheaply, and plastic or acrylic tanks are lighter and cheaper to ship than glass.

Check the seller's return policy before you buy. Some sellers offer free returns if the tank arrives cracked, but others don't. Read the reviews carefully—look for comments about packaging and whether the tank arrived intact. Prime shipping on Amazon can be faster, but it doesn't always explore to large or heavy items like aquariums.

Used tanks: Facebook Marketplace, Craigslist, and Nextdoor

Local classified sites often have used aquariums for $10 to $50, sometimes with filters, heaters, and decorations included. A 55-gallon tank that costs $150 new might be $60 used. The advantage is no shipping cost and the chance to inspect the tank before you buy. The risk is that used glass tanks can have small cracks you don't see until you fill them with water, or the seals may be failing.

Before you buy a used tank, ask the seller how long they owned it, why they're selling, and whether it currently holds water. If possible, ask to see it filled or ask them to fill it in front of you. Look for white mineral deposits or cloudy spots inside, which can indicate hard water stains but are usually harmless. Check the corners and seams carefully—cracks there are harder to spot but will leak. If you're buying local, you can pick it up yourself and avoid shipping costs entirely.

Specialty aquarium shops

Local aquarium stores usually charge more than big-box retailers, but they sometimes have sales on older stock or discontinued models. These shops are worth visiting if you want information on tank size and setup, though you'll pay for that informed in the price. Some specialty stores run clearance sales when they need to make room for new inventory—call ahead and ask when their next sale is scheduled.

Specialty shops are also the best place to find unusual tank sizes or high-end equipment if you're willing to spend more. They often have better customer service and can order specific items if they don't have them in stock. If you find a tank you like at a specialty shop, ask if they'll price-match a lower online price—many will to keep your business.

Timing your purchase: When prices drop

Aquarium prices fall at predictable times during the year. August and early September see back-to-school sales, when retailers discount starter kits and small tanks. November and December bring holiday sales, especially around Black Friday and Cyber Monday. January is also a good time because people return unwanted holiday gifts and stores clear inventory. Summer sales happen in June and July at some retailers, though prices are usually higher then because demand is up.

Watch for clearance tags at big-box stores—these are often the cheapest prices you'll find. Discontinued models and older tank designs get marked down to make room for new stock. Sign up for email alerts from Walmart, Target, Petco, and PetSmart so you know when sales start. If you're not in a hurry, waiting a month or two for a sale can save you $20 to $40 on a starter kit.

What to check before you buy

Whether you're buying new or used, inspect the tank for cracks, chips, and cloudy glass. Hold it up to light and look at the seams—these are the most common places for leaks to start. Check that the frame (if it has one) isn't bent or cracked. For used tanks, ask how old it is and whether it's been sitting empty or in storage, which can weaken the seals.

If you're buying a starter kit, make sure it includes a filter and heater—these are essential and expensive to buy separately. Check the wattage of the heater to make sure it's right for the tank size. A 10-gallon tank needs a 50-watt heater; a 20-gallon needs 100 watts. Read the filter specifications to confirm it's rated for the tank size. If the kit is missing these items or they're undersized, you'll end up spending more money later.

Frequently Asked Questions

Is it safe to buy a used aquarium?

Yes, if you inspect it first. Check for cracks, especially in the corners and seams, and ask the seller if it currently holds water without leaking. Used glass tanks are usually safe if they've been stored properly and haven't been sitting empty for years, which can dry out the silicone seals. If you're unsure, fill it with water in the seller's driveway before you take it home.

How much does it cost to ship an aquarium?

Shipping costs depend on size and weight. A 10-gallon glass tank costs $15 to $30 to ship. A 40-gallon tank costs $40 to $70. Plastic and acrylic tanks are lighter and ship for less. Always factor shipping into the total price before you buy online—sometimes a tank that looks cheap ends up costing more than buying it in a store.

Are starter kits worth buying, or should I buy the tank and equipment separately?

Starter kits are usually cheaper than buying each piece separately, especially at big-box stores. A $60 kit might include a 10-gallon tank, filter, heater, and light, which would cost $80 to $100 if you bought them individually. The downside is that kit equipment is sometimes lower quality than standalone pieces. If you want better equipment, buy the tank separately and upgrade the filter and heater.

What's the difference between glass and acrylic tanks?

Glass tanks are heavier, more durable, and don't scratch as easily. Acrylic tanks are lighter, cheaper to ship, and less likely to crack if dropped. Glass is clearer and lasts longer, but acrylic is better for small tanks you plan to move. For budget shopping, acrylic tanks ship cheaper online, while glass tanks are usually cheaper in-store because you avoid shipping costs.

When should I buy a tank if I want the lowest price?

August and early September offer the best prices because of back-to-school sales. November and December bring holiday discounts, especially around Black Friday. January is also good because stores clear holiday inventory. If you can wait, avoid buying in spring and summer when demand is higher and prices are up.