Congressional Aquarium
Freshwater Fish

Featured · Freshwater Fish

Bring your aquarium to life

Freshwater aquascapes, saltwater reefs, pond koi, and rare specimens—cared for by a team serving local hobbyists for 60 years.

Explore freshwater fish
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Altum Angelfish

Create. Discover. Explore.

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Freshwater Fish

Community, planted, cichlid, and nano aquariums

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Saltwater Fish

Marine fish, corals, and reef essentials

Freshwater
Marine & Reef
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Invertebrates - Freshwater and Saltwater

Freshwater shrimp and snails · Saltwater shrimp, crabs, and cleanup crews

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Koi & Ponds

Seasonal koi, pond plants, and outdoor pond care

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Rare Specimens

Monster fish, rare finds, and exclusive specimens — ask us about availability

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Freshwater Plants

Live aquascaping plants, carpets, stems, and mosses

Bettas & Nano Aquatics

Show bettas, nano aquascapes, gentle filtration, and specialized nutrition

Celebrating

60th Anniversary

1966 — 2026

Our Story

Six decades
beneath the surface.

A neighborhood landmark

Congressional Aquarium opened on the lower level of Congressional Plaza in Rockville and never left. Generations of Maryland, Virginia and DC families have walked the same aisles, started their first tanks here, and come back years later with their own children.

How we do things

Healthy livestock over volume. Honest answers over quick sales. We would rather talk you out of a fish today than have your aquarium fail the following week—so we test water, verify compatibility, and guide you every step of the way. If you’re successful — we’re successful.

60 Years in Rockville, MDFamily-run since day one
In-store services

Better water quality.Healthier aquariums.

Free water testing

Bring a sample; we’ll help interpret the results and identify the next practical step.

Aquarium setup guidance

We can guide you with tank selection, filtration, substrate, lighting, to help you meet your goals.

Compatibility checks

Confirm that your fish, invertebrates, plants, and habitat belong together.

Special orders

Ask our staff about hard-to-find livestock and specialty equipment.

Care guidance · Staff philosophy

“For 60 years, we’ve served Maryland, DC, and Virginia hobbyists—one tank, one conversation, one healthy fish at a time.”

Bring us a water sample, a photo, or a question. Our staff focuses on practical care, responsible compatibility, and helping every aquarium thrive long after the sale.

— The Congressional Aquarium staff