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CAA travel program

Fish & Tips

A Co-op Extension stalwart offers lessons in hydroponics, aquaculture—and life.


New York City’s Food and Finance High School is housed in a brick-and-concrete building in the Hell’s Kitchen neighborhood of Manhattan, several long crosstown blocks from the bright lights of Times Square. The massive structure, which takes up the better part of the block, is home to a half-dozen specialized high schools. Inside—past the friendly security guards and the metal detectors—it’s an institutional maze of wide hallways, heavy doors, and fluorescent lighting.


Photo by Kitty Kemp

But up on the third floor is an unexpected oasis: a room filled with lush herbs and lettuces whose leaves glow an otherworldly green under the simulated sunlight. In the heart of the city, the air smells intoxicatingly fresh.

The lab is the domain of agriculturalist Philson Warner, a thirty-five-year veteran of Cornell Cooperative Extension; so is the aquaculture facility in the basement, where thousands of tilapia and other fish swim in net-covered pools. Clad in a white lab coat and a paisley bow tie, Warner—the program’s founder—runs the Cornell-owned labs with an aura of benevolent strictness. Think of him as science’s kindliest drill sergeant.

Under his charge are some two dozen high school students enrolled in his program of hydroponics and aquaculture. Aside from the actual cleaning of fish, it’s no gut course. “I need nitrates done downstairs; where’s the nitrate guy?” Warner asks on a Thursday afternoon in late February, speaking in the lilting tones of his native Trinidad and Tobago. “Dissolve oxygen—I want two groups. I need to get at least five different kinds of lettuce seeds done. Remember your group. Water levels and pH—I need three guys. I need electrical conductivity done. I don’t want shortcuts. Shortcuts will result in dead plants and dead fish. Do you want to kill 10,000 fish?”


Photo by Kitty Kemp

The students, most of them African American or Hispanic, sport lab coats of their own. If they forget to bring theirs or it’s dirty, they have to leave—and more than two unexcused absences means a reduction in the $100 stipend they earn for participating. “Move around, guys. I want to see you. I don’t want you in back of me,” Warner tells the teenagers crowded into the hydroponics lab. “Let me say this again: you work in your station. I am not taking an excuse if something falls and breaks. You know how gravity operates. What’s the formula on gravity?” No one answers. “What’s the equation?” Still nothing. “Who remembers the equation on gravity, guys?” The silence stretches, the students gazing in the vicinity of their shoes. He finally answers for them. “Nine-point-eight meters per second squared. Things fall at that rate and guess what—they hit the ground. So don’t let me see anybody working at the edge of the station. I know you know, but I want to reinforce it.”

Over the years, more than 6,500 students have come through the program, either as visitors or participants; Warner has also trained more than 200 New York State teachers, who’ve brought the hydroponics technology back to their classrooms. The labs’ products—herbs like basil and oregano; a variety of exotic lettuces; the tilapia available whole or filleted; a Caribbean-style wet seasoning mix for meat and fish—are consumed at the school or sold to parents, teachers, and restaurants. They’re so popular with local chefs, Warner says, he has to ration them to keep things fair.

A decade ago, Warner ran an urban fish farm called Inner City Oceans; these days the aquaculture expert—who has spent more than four decades honing his technique—produces 60,000 pounds of tilapia a year out of the high school basement. “When you walk in here, you shouldn’t smell fish,” he notes, standing amid the blue plastic tubs and five-foot-tall microbead filters. “That would mean things were not balanced properly.”

Warner produces 60,000 pounds of tilapia a year out of a high school basement.In addition to the stipend, Warner’s students get 200 hours of community service credit, plus an official recommendation letter from Cornell to include in their college applications. For the high schoolers, the letter is a strong draw—but not the only one. “At first I came here because I heard it was a really good recommendation for college,” admits junior Tenzin Yangzom. “But after a while I enjoyed it.” Adds José Cespedes, a sophomore who took the course as a freshman but has come back for more: “It’s a great way to teach kids responsibility and get them interested in nature. It’s just good. It’s some serious fun.”

When the students arrive for each session, they’re expected to greet Warner formally, with “Good afternoon, professor.” In speaking to them, he refers to their classmates not as their peers or fellow students, but as their “colleagues.” There are hand-washing protocols and sign-in requirements, a prescribed path to take through the aquaculture lab’s foot-washing system, and myriad other strictures. In his firm-but-gentle way, Warner makes it clear that sloppiness and imprecision will not be tolerated, and that he’s not interested in excuses. It’s evident, even after a brief visit, that he’s not just training future researchers; he’s molding solid citizens. “Junior scientists always observe,” he tells them amid yet another set of instructions, then breaks into a smile. “I’m playing with you—but I’m serious.”