Freshwater Plants
Freshwater plants, substrate and fish in a variety of shapes and sizes
Saltwater Paradise
Salt water fish, invertibrates and corals of all types. Call today to check availability
Freshwater Fish and Plants
Assortment of fish from community to aggressive. We have beautiful nano specimens and the cichlisoma specimens you need

Welcome to Congressional Aquarium

Store Hours

Monday – Sunday: 12 – 6PM

Congressional Aquarium, Inc. carries a huge selection of rare freshwater and saltwater fish, aquatic plants, and aquarium supplies in Rockville, MD. Whether you’re new to the hobby, or an advanced aquarist looking to setup a beautiful reef ecosystem, we are the shop for you.


We order our fish from private wholesalers who value quality over quantity. Our fish are hand selected from freshwater farms in Georgia and saltwater distributors in California. We pride ourselves in quality. With tank isolation, preventative medication, and constant care, our staff can guide you in picking out beautiful healthy specimens for your aquarium.


Our staff are not just employees … they are aquarists like you and me! Our staff are there for beginners and advanced enthusiasts. Our staff can guide you in purchasing your new aquarium and help you install and setup an advanced lighting system and UV for your reef.


We are not your high volume big box store. We are a mom and pop store that prides itself in customer satisfaction. Whether you want to discuss plans or purchase quality equipment and specimens, we are here for you. We have a few new members who are ready and willing to help and we also have expert aquarists available to answer all of your technical questions.

We’re Hobbyists, Too!

Members of our staff have been working in this industry for many years, some as long as 45 years! We are not just employees, we’re enthusiasts and share our customers’ love for the aquarium hobby.

Aquariums & Tanks

We stock a number of different tanks, ranging from 1 to 125 gallons. Hard-to-find shapes and larger sizes are easily special-ordered and typically arrive within a week. To search for specific products please visit our wholesalers websites at Central Pet Distribution and Royal Pet Supplies.

Any equipment bought with the tank are 20% off, including decorations, filters, hoods, and lights! We are always ready to arrange for delivery, setup or maintenance of any size tank.