Your Local Experts for Live Saltwater & Freshwater Fish

Your Local Experts for Live Saltwater & Freshwater Fish

  • Aquarium tank with small fish, green plants, and a snake on the bottom.

    Splash Quarantine Fish Sale — 25% Off Wed–Fri

    New fish arrive weekly, offering a rotating mix of freshwater favorites and saltwater standouts. One of the best ways to add professionally acclimated fish to your tank.

    Visit the Shop
  • A display of fish tanks filled with various types of fish at a market or shop.

    Tropic Marin® Is Here

    Trusted by professional reef-keepers around the world, Tropic Marin® delivers unmatched accuracy in testing, dosing, and salt formulation. Whether you’re perfecting your parameters or maintaining long-term coral health, you can now find the industry’s most respected reef-care line right here at Big Fish Aquarium.

    Explore the Collection
  • A green telescopic lift truck with the label 'Sunbelt Rentals' is lifting a large wrapped pallet in an urban outdoor setting. The pallet is being positioned near a tree, with construction in progress in the background. Two workers are present, one operating the lift and the other observing, near a black metal fence and sidewalk.

    Chicago’s Trusted Aquarium Services

    Professional aquarium design, installation, and maintenance across Chicago and the suburbs. From freshwater to saltwater and reef tanks, we keep your aquariums healthy, beautiful, and hassle-free.

    BOOK NOW
  • A small snail resting on a rock surrounded by green plants.

    ONLINE ONLY SALES

    Exclusive online deals! Limited-time savings on cleanup crew and frozen food bundles

    🐠 Buy 3, Get 1 Free on Select Frozen Fish Food➜

    Monthly Promotions
  • A close-up of a fluorescent coral with elongated, tentacle-like structures glowing green and white, against a dark background.

    SALTWATER CORALS

    Vibrant. Resilient. Stunning.
    Handpicked for growing reef tanks.

    Add Color to Your Tank
  • Multiple orange and black patterned freshwater angelfish swimming in an aquarium.

    NEW FRESHWATER ARRIVALS

    Bright colors. Peaceful swimmers.
    Perfect for planted tanks.

    SHOP FRESHWATER

What are you searching for?

Trusted Brands for a Thriving Aquarium

Big Fish Aquarium is a premier aquatic pet store specializing in healthy live fish, custom reef tanks, and expert saltwater aquarium maintenance. Serving enthusiasts with the highest quality livestock and supplies since 2022, we invite you to shop our most trusted aquarium brands—selected by our team for quality and performance.

We carry top names like Fritz Aquatics, Ocean Nutrition, HYDROS, and Tropic Marin—known for reliable fish foods, water treatments, filtration, and reef care. Whether you’re running a freshwater tank or a saltwater reef, these brands are chosen for proven results and livestock safety.

Tropic Marin Professional STANDARD ICP Seawater Laboratory Analysis Tropic Marin Professional STANDARD ICP Seawater Laboratory Analysis Tropic Marin Professional STANDARD ICP Seawater Laboratory Analysis Tropic Marin Professional STANDARD ICP Seawater Laboratory Analysis
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Tropic Marin Professional STANDARD ICP Seawater Laboratory Analysis
from $35.00
Sicce XStream SDC Wave Pump (270 - 2250 GPH) Sicce XStream SDC Wave Pump (270 - 2250 GPH)
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Sicce XStream SDC Wave Pump (270 - 2250 GPH)
$250.00
Frozen Krill - Flat Packs Frozen Krill - Flat Packs Frozen Krill - Flat Packs Frozen Krill - Flat Packs
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Frozen Krill - Flat Packs
from $7.00
LifeRock Reef Forest Extension Kit LifeRock Reef Forest Extension Kit
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LifeRock Reef Forest Extension Kit
$275.00
Mystery Snail – Mixed Mystery Snail – Mixed Mystery Snail – Mixed
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Mystery Snail – Mixed
from $5.00
FRITZ EXPEL-F 20 COUNT FRITZ EXPEL-F 20 COUNT
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FRITZ EXPEL-F 20 COUNT
$21.00

TROPIC MARIN ®

〰️

SICCE

〰️

OCEAN NUTRITION

〰️

CORALVUE

〰️

TROPIC MARIN ® 〰️ SICCE 〰️ OCEAN NUTRITION 〰️ CORALVUE 〰️

JOIN THE BIG FISH MEMBERSHIP PROGRAM

Clownfish swimming in a dark blue aquarium with rocks and coral

SILVER

Included:

$5 coupon for livestock every month

10 gallons of free RO freshwater with $10 purchase

2-day warranty on fish out of quarantine

Free basic strip test

Learn more
A freshwater aquarium with various small fish swimming among green aquatic plants and a few dried leaves on the substrate, with some fish near a pinkish sponge or coral piece on the substrate.

GOLD

Included:

$10 Livestock coupon every month 

10 gallons of free RO freshwater with $10 purchase 

7-day guarantee on fish out of QT Free advanced water tests

5% Discount on all purchases

Learn more
Underwater scene with various green and purple aquatic plants

PLATINUM

Included:

$20 Livestock coupon every month 

10 gallons of free RO freshwater with $10 purchase 

7-day guarantee on fish out of QT Free advanced water tests

10% Discount on all purchases

Learn more

The Complete Aquarium Experience: Premium Live Fish & Expert Services

wysiwyg collector corals
Aquarium Supplies & Dry Goods
Freshwater and Saltwater aquarium fish livestock variety
Freshwater & Saltwater Livestock
Professional saltwater aquarium water testing and maintenance service
Expert Services & Maintenance
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Colorful tropical fish swimming among coral and rocks in an underwater reef scene.

Join the Big Fish Community

Dive into the conversation! The Big Fish Aquarium Forum is where local hobbyists, reef enthusiasts, and beginners alike come together to ask questions, share tank setups, and trade advice. Whether you’re troubleshooting water chemistry or showing off your latest coral addition, this is your space to connect and learn from fellow aquarists.

Learn more

Chicago Aquarium Services & Design

Why Choose Big Fish Aquarium?

Verified Livestock: Every fish is quarantined and inspected for health to ensure a thriving start for your aquarium.

Custom Reef Consulting: We design and install professional-grade reef systems tailored to your space and lifestyle.

Professional Water Testing: On-site analysis for pH, salinity, and nitrates. Learn about Saltwater Chemistry and how we maintain perfect parameters for our clients.

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