Congressional Aquarium on Rockville Pike has been a fixture of the Maryland aquarium scene for years — the kind of store that feels like it's been there forever, with the institutional knowledge to match. Walk in and you'll find a surprisingly large space packed with tanks, supplies, spare parts for pumps and filters, and a fish selection that dwarfs anything at the Petco across the street. Freshwater is where this store truly shines.
Reviewers consistently praise the African cichlid selection as outstanding, and the variety of live plants has helped hobbyists build thriving planted tanks months after purchase. C. metro area.
Staff member Ana has earned a devoted following for her patience with newcomers setting up their first tanks, while Nicholas has been praised for guiding customers through community tank stocking decisions. There's also a pond section with koi and pond plants for outdoor enthusiasts. The saltwater side tells a different story.
Multiple visitors have reported neglected marine tanks with cyanobacteria outbreaks and empty displays — this is fundamentally a freshwater operation, and reef hobbyists should set expectations accordingly. The betta section also draws criticism for relying on the cup system rather than individual micro tanks. Pricing is the elephant in the room.
Nearly every reviewer acknowledges that Congressional Aquarium charges significantly more than chain stores, online retailers, and even neighboring independent shops. You're paying a premium for the expertise and the curated selection — whether that trade-off works depends on how much you value in-person guidance and immediate availability of specialty items like swim bladder medications that PetSmart simply doesn't carry. Service experiences vary wildly.
Some visits yield deeply attentive, knowledgeable help; others involve being collectively ignored by clustered staff. Current hours run noon to six daily. Come for the freshwater selection and the veteran advice — just budget accordingly.
Ben Havilland
56 reviews
Great selection but many times when we’ve gone there the staff straight up ignores you. I’ve literally asked for help straight to an employee’s face, they stop making eye contact and walk another direction. Last time I was here the staff was all grouped together talking and they all collectively ignored me and don’t look at me and then argued amongst themselves as to who would help me. They finally decided it would be none of them and got the person from the shrimp station to help us with some reef fish. Once helped he was very friendly. Just a weird and off putting experience. We spent about $200 that day but almost walked out.
Luis Vasquez
14 reviews
The best 👌 in costumes service Better than pet smart
John Qiang
24 reviews
I never bought anything there because they are so over priced, really expensive. Last time I went there, I thought they were out of business, almost half of the tanks were empty and the saltwater display tank was covered with a thick layer of algae.
Matthew Warren
67 reviews
Edited: Improved review now that hours match reality. Update your hours. 12-6 every day. Also expensive, do have nice selection.
Joe Swan
47 reviews
I was so excited to come here and it’s nice and clean BUT extremely expensive! They are 3x more expensive than the neighboring private fish stores.
Som Bahrami
54 reviews
This is the best and most knowledgeable place for any fish tank related items. The variety of fish you can get from this store is uncomparable with any other aquarium in the area and to make things even better the staff are extremely knowledgeable and helpful. Plus you get to support a local business against the big box stores
C T
6 reviews
Great place ! Staff is knowledgeable and always points me in the right direction!
Abby R
8 reviews
Pierogi the piranha is very happy with his new setup! Staff were helpful with getting us all the items we needed to renovate our fish tank.
Annette Hibbert Nelson
3 reviews
What a fantastic place! I brought in my small aquarium with a ton of issues and they helped fit it right up! The store is surprisingly large and has a great selection of everything you need for an aquarium. The knowledgeable employees are much more helpful than at the large big box stores. I’ll be back!
William L. Hawkins (Bill)
42 reviews
This store has a huge inventory of just about whatever you might need, from chemicals, equipment, plants, and a wide assortment of fish. However, after shopping online, at several local Petco and Petsmart locations, this place has the highest prices of any others, including online, Chewy, Walmart, and Amazon. And, this is for basic aquarium supplies ... absolutely a place to check ... but compare prices of others before you go, that is if the dollar is of any importance.
Note: Store information and services may change. Always call (301) 881-6182 to confirm current availability, hours, and services before visiting Congressional Aquarium.
Phone
(301) 881-6182Website
congressionalaquarium.com/Address
138 Congressional Ln, Rockville, MD 20852
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138 Congressional Ln, Rockville, MD 20852
February 7, 2026
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