“There they are, those dark humps,” he says with a smile. “They’re up to their noses in the water today.” No sooner has he finished his sentence than three large water buffalo slowly trudge out of the pond. Their calm, however, quickly vanishes when they recognize their owner. After all, he might have some tasty food for them. He stops by every two days to feed them.

The three “girls” are all that’s left of a herd that was once much larger. In 2008, Tusche acquired the first water buffaloes to serve as natural lawnmowers for the areas along the banks of the ponds. They sold the meat in the farm store, where fish is usually the main item sold. At its peak, there were 13 animals. Today, the ladies are primarily an attraction and a surprise for walkers who expect to see waterfowl or fish by and in the ponds. The latter is actually Tusche’s area of expertise. As part of this year’s Lusatian Fish Weeks, which take place from September 26 to November 1, he has been named Pond Owner of the Year.

Carp Beats Science
Tusche’s parents are from Upper Lusatia, specifically Viereichen. In 1980, they moved to Frankfurt/Oder, where Helmut Tusche worked for what was then ZBE Satzfischproduktion. Just one year later, their son Karsten was born. “After the fall of the Berlin Wall, my father immediately started his own business,” he recalls. His father leased the group of ponds in Hammerstadt but continued to live with the family in Frankfurt. “I basically grew up among fish,” Karsten Tusche continues. From an early age, he learned how much work goes into getting a carp onto the plate—and what worries his father faced when heat or disease took a toll on the fish. He also knew that the job often meant eight, and sometimes even twelve, hours of work per day.

He never felt any pressure to join his parents’ business. Nevertheless, after graduating from high school in 2001, he decided to study agricultural and fisheries sciences in Berlin. Fish would become his profession—but initially in a way quite different from what he’d imagined. He stayed in academia and earned his Ph.D. in fish nutrition. At the Fisheries Research Institute in Büsum, he studied how trout could be fed potatoes. Today, potato protein is a common ingredient in fish feed mixes. “But a career in research means thinking in terms of one project after another, one round of funding after another,” he says. Ultimately, that wasn’t for him.

Karsten Tusche likes that, at the end of the day, he can see what he’s accomplished. He likes that pond farming follows the cycle of the year, with all its ups and downs. He likes that he can be out and about, close to nature. Even during his time in research, he continued to support his father from afar. In 2011, he finally returned to Rietschen and joined the business shortly thereafter.

Insatiable Pests
It all began with the Hammerstadt pond complex. There, the structure remains the same as it was 400 years ago—completely traditional, with no electrical connections to the ponds and no aeration systems. Later, the ponds in Rietschen and Deuben were added, followed in 2017 by Reichwalde with about 30 hectares. Today, the Rietschen Fish Farm manages a total of 42 ponds covering 260 hectares. Tench, perch, roach, and zander thrive there. But the most important fish remains the mirror carp. They take three to four years to reach market size before being sold. The Tusche family and their team produce around 130 metric tons each year. Karsten Tusche has been a partner and managing director of the business since 2024. His father primarily oversees the company’s operations near Frankfurt/Oder.

He admits that his workload hasn’t gotten any lighter as the boss. There’s a lot to do—at the pond, of course, and also in the office. Landscape and waterway maintenance are also part of his job description. Animal “architects” like beavers or the invasive nutria, which eat important vegetation and erode the bank reinforcements, make his job even more difficult.

“Eight to 14 percent of a pond’s surface area should be a closed reed belt so that fish or waterfowl can hide from predators,” he explains. For some ponds, however, that proportion is now below three percent. He has nothing against protecting beavers. “But we need to rethink our approach if this poses a massive threat to other animal species.”

Fish available until just before the start of summer
The Rietschen Fish Farm sells a good portion of its fish production in its farm store. The entire team pitches in there to get the fish to customers. Tusche enjoys the direct contact with customers—the brief conversations about work at the pond or the best carp recipe. The shop is open Fridays from 8 a.m. to 3 p.m. or 5 p.m. and Saturdays from 8 a.m. to 11 a.m. Smoked fish is also available.

Since part of the catch is frozen, fish is still available until just before the start of summer. Then everyone waits for the fall harvest. “We also deliver a large portion to Mecklenburg-Western Pomerania.” “Where it says ‘Müritz fish’ on the label, it could just as well be ‘Upper Lusatia fish’ inside,” he adds with a smile.

Karsten Tusche has already passed on his passion for fish to the next generation. His children, aged seven and 13, have grown up with the business just like he did. Will they take over the fish farm someday? Does their father even want them to? “The kids are still growing up, and they should first figure out for themselves where life is taking them.”

Ten or 20 years is a long time. The question is whether such a business will still be worthwhile by then. By the spring of 2026, climate change had already caused the water level in the ponds to drop a good half meter below normal. It’s a challenge that could grow even greater in the coming years. “I’d hate to roll out a carpet with holes in it for my children.” For him, this is his dream job right now. “The next generation is welcome to have one of their own.”

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