The best online aquarium supply stores are generally Chewy, Amazon, Marine Depot, BRS (Bulk Reef Supply), and LiveAquaria, depending on what you're buying. Chewy and Amazon carry most staple supplies at competitive prices with fast shipping. Marine Depot and BRS specialize in saltwater and reef products with deeper inventory and knowledgeable customer support. LiveAquaria is the standout for buying live fish and coral online, with a livestock guarantee most competitors can't match.
Shopping for aquarium supplies online beats the local fish store for most equipment, but not everything. Price, selection, and the ability to read reviews before buying are major advantages. The disadvantage is wait time, which matters when you're dealing with a tank emergency. Knowing which stores excel at what, and what to watch for in shipping policies, makes a significant difference in your experience. Here's what I've found after buying equipment and livestock across most of these platforms.
The Major Online Aquarium Retailers
Chewy
Chewy has become one of the dominant players in pet supplies, and aquarium gear is no exception. Their selection covers dry goods thoroughly: filters, heaters, test kits, food, substrate, and standard equipment. Prices are competitive, often matching or beating Amazon, and their auto-ship discount (typically 5-10% off repeated orders) adds up over time on items you buy regularly like fish food, filter media, and dechlorinator.
Chewy's standout is customer service. Their support team regularly replaces defective products without hassle and has a reputation for sending sympathy cards when customers lose a pet, which speaks to the culture.
Where Chewy falls short is specialized reef equipment. You won't find a full selection of protein skimmers, calcium reactors, or dosing systems there. For standard equipment, it's excellent.
Amazon
Amazon's aquarium selection is enormous but inconsistent. You'll find the same Fluval, API, and Marina products you'd find at a fish store, alongside a large volume of generic no-name products from overseas manufacturers. The quality varies dramatically. An API Master Test Kit from Amazon is exactly the same as anywhere else. A $12 generic HOB filter from an unfamiliar brand is a gamble.
The advantage is speed. Prime shipping often gets products to you the next day, which matters when a heater fails and your tank is dropping temperature. Amazon also carries discontinued products that specialized retailers have moved past.
Read reviews carefully on Amazon and look for reviews mentioning specific model numbers or purchase dates. Older reviews on products that have had quiet reformulations can be misleading.
Marine Depot
Marine Depot specializes in saltwater and reef. Their selection of skimmers, sumps, refugium lighting, dosing equipment, RODI systems, and coral food is far deeper than any general retailer. The BRS-307 Reactor from BRS is sold there, alongside major brands like Apex, Tunze, Royal Exclusiv, and ATI.
Marine Depot runs regular sales and has knowledgeable staff who can help with product selection questions. For reef keepers, it's one of the first stops for equipment research even if you buy elsewhere.
Shipping costs more for heavy items like sumps or large skimmers, but that's true anywhere. They offer free shipping on orders over $79, which applies to most equipment purchases.
Bulk Reef Supply (BRS)
BRS is the reef hobby's most educational retailer. Their YouTube channel has thousands of hours of content explaining reef chemistry, equipment selection, and tank builds, and the store inventory backs it up. They carry their own BRS brand products (including highly regarded two-part calcium and alkalinity supplements), plus most major reef equipment brands.
BRS is particularly strong for consumables that reef keepers buy repeatedly: salt mix (they sell Instant Ocean, Red Sea, and Fritz in large buckets), RODI replacement filters, activated carbon, GFO (granular ferric oxide), and two-part dosing solutions. Their bulk pricing on these items saves meaningful money over time.
They also carry aquacultured coral frags through their Aquacultured Coral program, though LiveAquaria remains the stronger livestock specialist.
LiveAquaria
If you're buying fish, invertebrates, or coral online, LiveAquaria has the strongest livestock guarantee in the business. Their Divers Den section features hand-selected, photographed individual fish and coral with a 14-day live arrival guarantee. They ship via FedEx Overnight with heat or cold packs depending on the season.
The Diver's Den section is worth bookmarking if you want specific fish or unusual specimens. You're buying the exact animal in the photo, not a representative example from a batch.
For plants and freshwater livestock, Planted Aquatics is a strong alternative, and for specialty freshwater fish, Aquatic Arts has an excellent reputation for healthy, well-quarantined stock.
What to Look For in an Online Aquarium Store
Beyond brand name, a few factors separate reliable online stores from problematic ones.
Livestock Guarantee
For live plants, fish, coral, or invertebrates, a live arrival guarantee is non-negotiable. Look for at least a 7-day guarantee, with 14 days being better. The guarantee should clearly state the process for claims (usually a photo of the animal within a set time window and a refund or store credit). Stores without a stated guarantee are a risk.
Return Policy on Equipment
Most quality retailers accept returns on defective equipment. Check the return window (30 days is standard) and whether return shipping is covered for defective products. Chewy and Amazon generally have the most painless return processes.
Shipping Temperature Management
Livestock shipped in summer needs cold packs. Livestock shipped in winter needs heat packs. Reputable stores choose packing based on current weather in both origin and destination zip codes. Some ask for your shipping preference at checkout. If a store doesn't mention temperature management for live animals, that's a warning sign.
Customer Reviews and Forums
Before ordering from a smaller or unfamiliar online store, check reviews on Google, Trustpilot, and reef forums like Reef2Reef or The Planted Tank. The aquarium hobby community is vocal about good and bad buying experiences. A store with consistent complaints about DOA (dead on arrival) livestock or slow shipping is one to avoid even if prices look good.
Saving Money on Online Aquarium Supplies
Auto-Ship Programs
Chewy's auto-ship discount is 5-10% on most products. For recurring purchases like Seachem Prime, API test kits, and fish food, this adds up. You can pause or cancel auto-ship anytime. Amazon's Subscribe and Save program works similarly.
BRS Subscription for Reef Consumables
BRS sells two-part calcium and alkalinity supplements, RODI filter replacements, and activated carbon in quantities that reduce per-unit cost. Buying a 10-pack of RODI membrane replacements instead of one costs more upfront but saves significantly per replacement.
Sales Cycles
Marine Depot and BRS run substantial sales events around Black Friday, and both do periodic equipment sales throughout the year. If a major purchase isn't urgent, waiting for a sale can save 20-30% on large items like protein skimmers, wave makers, or lighting.
Comparison Shopping
Use Google Shopping to compare prices across retailers for the exact product you want. Filter and heater prices vary by $10-30 between retailers on the same model, and that gap widens on more expensive items. For best-reviewed products across different categories, our Best Aquarium Supplies Online guide covers what's consistently worth buying.
When to Use Your Local Fish Store Instead
Online buying has limits. For emergencies (your filter failed tonight), a local fish store is the answer. For livestock, seeing fish in person before buying is always better than photos. A sick or stressed fish is much easier to identify in person.
Local fish stores also often have access to locally bred fish and livestock that never appear online, and the ability to ask questions in real time about compatibility and care from staff who know their inventory is genuinely valuable.
For the best online-only shopping resources and product comparisons, see our Best Aquarium Supply Online Store guide.
FAQ
Is it safe to buy fish online? Yes, from reputable stores with live arrival guarantees. LiveAquaria, Aquatic Arts, and similar specialty retailers ship overnight with proper temperature management. You should expect a small number of losses over many orders, which is why the guarantee matters.
Which online aquarium store has the best prices? It depends on the category. Chewy and Amazon are competitive on dry goods and standard equipment. BRS wins on reef consumables in bulk. Marine Depot is strong for specialized reef equipment. No single store wins across all categories, so comparison shopping pays off.
Can I get aquarium plants shipped online? Yes. Planted Aquatics, Buce Plant, Aquarium Co-Op (through their online store), and Amazon sellers all ship aquatic plants. Plants ship better than fish because they tolerate lower temperatures and don't need aeration during transit.
What should I look for in a livestock live arrival guarantee? At minimum: a stated time window for reporting DOA (usually within 2-24 hours of delivery), clear instructions for making a claim (typically a photo), and a replacement or store credit as the remedy. A 14-day guarantee is meaningfully better than just live arrival because it covers losses during the acclimation stress period.
Key Takeaways
Chewy and Amazon handle most standard dry goods well. Marine Depot and BRS are the places to go for serious reef equipment and consumables. LiveAquaria is the strongest for livestock with the best guarantee. Before buying from any unfamiliar online store, check reviews on Reef2Reef or The Planted Tank forums. Auto-ship programs and bulk buying reduce costs on items you purchase repeatedly.