I read your recent column on the lost buildings on the Mall, including the Fisheries Building. I have distinct memories of my grandparents taking me to an aquarium in the basement of the Commerce Department building at 14th Street and Pennsylvania Avenue NW. This would have been in the early 1970s, long after the Fisheries Building was demolished. I have often wondered what happened to that small, out-of-the-way aquarium.

Amy Worden, York Springs, Pa.

Looking at captive fish does not, at first blush, seem that exciting. There’s not much thrill at second blush, either. And yet Answer Man has become increasingly captivated by places where Washingtonians could once gaze upon our finny friends.

Starting around 1879, such species as carp, bass and shad were bred by the U.S. Fish Commission in large ponds just west of the Washington Monument. (N/A/Historical Society of Washington, D.C)

That history includes the National Aquarium, which, until it closed in 2013, was housed in the Commerce building. But we’ll get to that next week. First, Answer Man wants to explore the acres of fish ponds that once sat between the Washington Monument and the Potomac.

In the summer of 1879, ponds started to be carved out in the area then known as the Potomac Flats. The ponds were the idea of Spencer F. Baird, a former Smithsonian curator — and future Smithsonian secretary — who had been tapped by President Ulysses S. Grant to head the U.S. Fisheries Commission.

Baird noted the decrease in fish harvests across the country — due, he believed, to overfishing — and thought a breeding program could help replenish stocks. Such wild species as shad, bass and crappie would eventually be raised in the Washington Monument ponds, but the early attention was focused on a foreign fish: the carp.

To be the Adams and Eves of his piscine Eden, Baird imported 65 hybrid carp from Germany.

Carp proponents insisted that the fish was “a valuable domestic animal, tenacious of life, easily cared for, and assuring profitable returns. It is of prodigious fecundity, lives, if undisturbed, to a good age, and may be fattened like pigs to a great weight in a short time.”

True, maybe, but carp didn’t actually taste all that good to American palates. Worse, it spread like mad in U.S. waters, threatening native fish.

But that realization — and the carp-eradication efforts that followed — were far in the future. Back in the 1880s and 1890s, carp were cool.

Answer Man thinks the fish ponds may have looked something like Kenilworth Aquatic Gardens, but with a bit of a factory air. There were a half-dozen large ponds. Some were fringed with Indian corn and pampas grass. Lotus and other aquatic plants bloomed in the water. Turtles lazed.

Fish from the Monument ponds were used to stock lakes and rivers up and down the East Coast. Americans could even write to their representative and order their own fry, delivered in a can similar to a milk can and holding about 20 fingerlings.

Bizarrely, they could also get free goldfish, which the Fish Commission bred. In the 1890s, Congress was sending out 20,000 goldfish a year, and it was estimated that nearly a third of the houses in the District had a free federal fish.

There were challenges. Floods swamped the ponds in June 1889, sweeping no fewer than 4,000,000 baby fish into the raging waters of the Potomac. Wrote one reporter: “In the annals of fish culture no such disaster has previously been recorded.”

There were dangers. Rudolph Hessel, a fish expert imported from Germany to oversee the ponds, kept guns on site to dispatch the hawks, herons, kingfishers and snakes that snacked on his charges. (Hessel also had a South American spider monkey named Chicky.)

Answer Man likes this 1880 description of the Monument ponds: “The solid sod slopes so greenly down to the water, and in these early spring days one would rather sit on the grass in the sunshine than to breathe the breath of the galleries and listen to Congressional debate. The sun shines; the warm, cloudy water is full of lights and shadows; there is a dandelion within reach; the flags in the water are taking on new shades of green; now and then there is the flash of a fin, and a shy carp swims away from you . . . ”

When the Potomac started silting up, threatening shipping in and out of Georgetown, the river bottom was dredged. The spoils had to be put somewhere. By 1912, the ponds were filled in.

Next week: Answer Man dips into the aquarium.

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