The best online fish supply stores for most hobbyists are Amazon, Chewy, and specialty retailers like LiveAquaria, Marine Depot, and Aquarium Co-Op's online shop. Each serves a different purpose. Amazon and Chewy are your go-to for dry goods and consumables like filters, heaters, food, and chemicals, with competitive pricing and fast shipping. Specialty aquarium retailers shine when you need specific livestock, rare equipment, or expert-sourced products that the big retailers do not carry. Knowing which store to use for what saves you time and money.
This guide breaks down what each type of online store is good for, what to watch out for, and how to compare prices and product quality before hitting checkout.
General Retailers vs. Specialty Aquarium Stores
The aquarium hobby has two distinct categories of online retailers, and they serve different needs.
General Retailers (Amazon, Chewy, Petco Online)
Amazon carries virtually every major brand of aquarium equipment and ships most items in one to two days. If you need an Aqueon QuietFlow filter, a Fluval canister, API test kits, or Hikari fish food, Amazon almost certainly has it at or near the lowest price available. The Prime shipping on large or heavy items is particularly valuable since aquarium gear is heavy.
Chewy positions itself as the pet-focused alternative. Chewy carries all the standard equipment brands alongside a robust selection of livestock food, additives, and treatments. Their autoship subscription (similar to Amazon Subscribe and Save) gets you an additional 5% off recurring purchases, which adds up if you buy a lot of fish food, water conditioner, or salt mix. Their customer service is unusually good for a large retailer.
Petco's online store fills in the gaps when you need something specific to their house brands (like Imagitarium tanks and accessories) or when a same-day pickup from a local store is available.
Specialty Aquarium Online Retailers
These stores cater to serious hobbyists and carry products you will not find at big-box retailers.
Aquarium Co-Op (aquariumcoop.com): Run by YouTuber Cory McElroy, this Washington-based retailer focuses on freshwater fish and plants. Their own-brand products (sponge filters, hang-on-back filters, fertilizers, and the popular Easy Green liquid fertilizer) are consistently well-reviewed. They also ship live plants and fish, with a solid DOA (dead on arrival) guarantee. If you keep planted tanks, this is a go-to.
Marine Depot (marinedepot.com): One of the largest saltwater-focused online retailers. Carries equipment brands that general retailers often do not stock, including Reef Octopus protein skimmers, Radion LED fixtures, GHL controllers, and Apex Neptune systems. Pricing is competitive and they frequently run sales that beat Amazon on specialty reef equipment.
LiveAquaria: The online arm of Drs. Foster and Smith, now part of Petco. LiveAquaria is best known for livestock, particularly their Divers Den section, where individual animals (fish, corals, invertebrates) are photographed and described so you know exactly what you are getting. They have a good DOA policy and the livestock quality is generally high.
Bulk Reef Supply (BRS): Focused almost entirely on reef aquariums. BRS sells their own brand of two-part calcium and alkalinity dosing solutions, media, and equipment alongside major brands. They also have an enormous library of video content that helps you understand what you are buying and why.
For a curated look at the best products across all categories, the best online fish supply store roundup covers rated retailers with specific strengths broken down by product type.
What to Buy Online vs. In-Store
Some items are always better purchased online. Others carry risks that are easier to manage in person.
Always Buy Online
Dry goods are the clear winner for online purchasing. Filters, heaters, lights, pumps, test kits, water conditioners, foods, and consumables all ship safely and are cheaper online than at most local fish stores, which typically mark up hardware by 30 to 50%.
Specialty chemicals and treatments are also ideal for online purchasing. Seachem's product line (Prime, Stability, Excel, Flourish), API test kits, Brightwell Aquatics products, and similar items are available at significant discounts online compared to local stores.
Equipment that you are buying based on specs rather than physical inspection, such as a canister filter with documented GPH ratings, is perfectly safe to buy online. You know exactly what you are getting.
Buy In-Store or From Specialty Retailers With Photos
Livestock is the area where local stores have an advantage. You can see the fish before you buy, which means you can assess health, coloration, and behavior. When buying fish online, use services like Divers Den at LiveAquaria or reputable eBay sellers who provide photos and guarantees.
Live plants are variable in quality online. Low-tech plants like Java fern, Anubias, and Java moss ship well and are generally reliable from Aquarium Co-Op and similar specialty shops. Delicate stem plants can melt in transit if shipping is slow.
Shipping Costs and Timing
Shipping is where online fish supply purchases can get expensive. Here is what to watch for.
Heavy items like large filters, canister units, and sump equipment have high actual shipping weights. Amazon Prime absorbs this cost, but on specialty sites, a $100 filter may arrive with $20 in shipping added. Always check the final total, not the list price.
Most specialty aquarium retailers offer free shipping above a threshold, typically $50 to $75. Planning your orders to hit these thresholds is an easy way to save.
For livestock and live plants, two-day shipping is the minimum you should accept. Three-day-or-longer shipping increases mortality significantly, especially for sensitive species. Check the store's live arrival guarantee and understand what it covers. Some stores only guarantee live arrival during certain temperature windows, meaning they will not ship fish during the hottest summer months or coldest winter months.
Reading Product Reviews and Identifying Fakes
Amazon's review system is useful but imperfect. Aquarium equipment categories have a problem with clone products and fake reviews. Here is how to shop smart.
Filter out reviews under 4 words. Use the Keepa Chrome extension to check price history on Amazon; steep recent discounts often precede a review incentive push. For any pump, heater, or filter, search the model name on a dedicated aquarium forum like Fishlore or Reef2Reef to see what actual hobbyists report about long-term reliability.
Stick to brands with reputations in the hobby. For filtration, that means Fluval, Eheim, Aquaclear, Seachem, and Hydor. For lighting, Finnex, Fluval, Current USA, and Kessil. For reef lighting, Radion and AI (Aqua Illumination) have excellent track records. Less-known brands on Amazon can be fine, but verify them on forums before committing to expensive purchases.
Price Comparison Strategies
Prices on aquarium equipment shift constantly. The same Fluval FX4 filter can vary by $30 to $50 between retailers within a week.
The most efficient approach is to use Google Shopping with your specific product name. This pulls current prices from all major retailers simultaneously. For recurring purchases, set a price alert on CamelCamelCamel (Amazon price history tracker) so you buy water conditioner and food at the lowest prices rather than paying whatever the current list price is.
Specialty retailers like Marine Depot and BRS run periodic sales that beat Amazon prices on high-end equipment. Signing up for their email lists gets you early access to these sales.
For common consumables like water conditioner, fish food, and salt mix, the Subscribe and Save discount on Chewy or Amazon often results in the lowest ongoing cost.
For guidance on aeration equipment you might add to your setup, the best oxygen machine for fish tank article covers air pumps and aeration options with current pricing.
FAQ
Is it safe to order live fish online?
Yes, if you use reputable vendors with strong DOA guarantees and appropriate shipping methods. Look for stores that use heat packs in winter and ice packs in summer, ship with two-day or overnight delivery, and have clear, documented guarantee terms. LiveAquaria's Divers Den section and Aquarium Co-Op are reliable for livestock. Avoid sellers without photos of the actual animals or without any guarantee language.
Why are online prices so much cheaper than local fish stores?
Local fish stores carry overhead costs that online retailers do not: rent, utilities, staff, and the cost of maintaining livestock in store tanks. These costs are real and explain why local stores charge more for dry goods. That said, local stores provide value that online retailers cannot: you can see what you are buying, get expert advice from staff who know their inventory, and take home a healthy fish the same day. Both have their place in the hobby.
What brands should I trust for aquarium equipment online?
For filtration: Fluval, Eheim, Aquaclear (Hagen), Seachem. For heaters: Eheim Jager, Aqueon Pro, Cobalt Aquatics. For lighting: Finnex, Current USA, Fluval, Kessil, Radion. For food: Hikari, New Life Spectrum, Northfin, Repashy. These brands have earned consistent positive reviews from hobbyists over years.
Are there aquarium subscription boxes worth buying?
A few exist, including AquaBox and similar services. They can introduce you to new products, but the value depends heavily on what you already have. For established hobbyists, the items in subscription boxes often duplicate what you already own. For beginners, they can be a good way to try different brands of food, treatments, and accessories without committing to full-size purchases.
The Bottom Line
Use Amazon and Chewy for everyday equipment, food, and consumables. Use specialty retailers like Marine Depot, Bulk Reef Supply, and Aquarium Co-Op when you need specific products, reef equipment, or quality live plants. Always check shipping costs before finalizing orders, read reviews on aquarium forums rather than relying solely on retailer reviews, and compare prices across a few sources before buying anything over $50. That approach consistently gets you the best products at the best prices.