My fish are dead. First one black molly went belly up, and then the other two later that same day. The next morning I found the flame tetras floating lifeless, mid-tank, all three of them.

It’s my fault. I knew that Mr. Newman was just crossing his fingers for me when he sold Dad and me the fish before I had set up my aquarium. Now it’s just Victor in the tank.

So I’ve started over. The fish went down the toilet, along with the water in the aquarium. I washed the gravel, reanchored the plants, and gave Victor a new place to stand. I added fresh water and treated it with special drops, using the instructions in my new Bible, Handbook for the New Aquarist. The water turned cloudy at first, but then cleared up fine—just like the book said it would. The temperature has been around seventy-five degrees Fahrenheit for five days. This aquarium is ready for fish.

It’s Saturday, and Dad drops me off at Tanks for You while he takes care of some errands. “Is half an hour too long?” he asks before we go our separate ways.

“No. Don’t hurry,” I say. I could use an hour in the store. I’m going to take my time because I’m doing things right this time. I hope Mr. Newman isn’t here. I think we’d both be embarrassed if I had to tell him that the fish died.

“Hey, Gabe!” Dominique greets me. “I know you’re careful, buddy, but you didn’t have to wait this long to get your fish!”

It’s been three weeks since I bought my aquarium. Dominique doesn’t know what I did, and I guess I don’t have to tell him, but I confess anyway. If he’s disappointed, he doesn’t show it.

“Yeah,” he says as he nods slowly, “fish’ll die on you. It happens to us all.” He pops his chewing gum, which I’ve noticed he seems to do when he’s thinking. “Did they have white spots when they died?”

I try to remember. “I don’t know,” I admit.

“Maybe they had icky,” he says—or at least that’s what I think he says.

I laugh. “Maybe they were icky?”

Now Dominique flashes his teeth. “No, man, fish are never icky, not to me. Maybe they had ichthyo. It’s a very common fish disease. They get white spots.”

I try to remember again. “I don’t think they had spots.”

“Overfeeding?”

“Nah,” I say. I know enough not to overfeed fish. I never gave the mollies and tetras more than they could eat in two or three minutes. I’m pretty sure there wasn’t any uneaten, decaying food polluting my tank.

“Hmm,” Dominique says. “Well, sometimes you just don’t know.”

“I guess the tank wasn’t ready,” I say.

“Could be,” he says. “It’s a little ecosystem, and it can be delicate.”

I nod. Don’t I know it.

“But it’s ready now?” Dominique asks.

“It’s really ready,” I say. “And I think I’d like something more interesting than black mollies and flame tetras. I just got those the first time because they’re supposed to be hardy.”

“Something more interesting?” Dominique is walking down the aisle looking into the display tanks that hold fish that are for sale.

“Like a clown loach,” I say. “They’re kind of goofy-looking, but it might be fun to have one. And a couple of Siamese fighting fish would be cool. And, well, I like angelfish, and the blue gourami is a good fish.” I’m walking among the display tanks, too, as I talk.

“They’re all good fish,” Dominique agrees. “But, you know, fish are a little like people. You can’t just throw them together and expect everyone to get along.”

Now I remember some of the pointers in my handbook. “Oh, right,” I say, “I can’t have a pair of Siamese fighting fish. They could kill each other.”

“But you can have one,” Dominique says, “and it will leave other types of fish alone.”

And clown loaches, I remember, like company. A single clown loach might actually die of loneliness.

“And you have to think about traffic patterns, too,” Dominique adds. “The clown loaches like the bottom part of the tank, and angels hang out in the middle. Tetras like the middle, too, and they’re small so they might look nice in there with a few angels. Try a different type of tetra this time.”

I settle on two large angelfish, two clown loaches, six head-and-tail-light tetras, and a sucker-mouth catfish, which will scavenge for food on the bottom of the tank and help keep the aquarium clean. The angelfish are white and light purple with black stripes, very tall and not very long. The clown loaches are orange with black rings around their bodies and over their eyes, which make them look like clowns. Bright yellow spots on the tetras give them their name, head-and-tail-light. I think these eleven fish will make a fine community. For now, I decide to pass on the Siamese fighting fish.

While Dominique and I are gently putting the fish in plastic bags for their ride home, the door opens and a customer comes in.

“Mr. Wheeler!” Dominique calls. “How’s the reef tank?”

It’s Amy Wheeler’s father. “Always a challenge, Dominique,” he answers.

I’ve heard about reef tanks. They’re saltwater aquariums for corals, which are tiny animals that build rock-like reefs with their skeletons. Reef tanks are kind of complicated to set up and keep going. They’re for real experts.

“Hi, Gabe,” a familiar voice says.

I look toward the door. It’s Amy, who has just walked in to join her father.

“Hi, Amy,” I say. “Here with your Dad?” No, idiot, I say to myself. She’s here with Albert Einstein.

But Amy just says, “Yup. He needs some kind of doodad for his tank.”

“The reef tank,” I say.

“No, the other one,” Amy says. “He has another salt-water tank, the one with fish.”

“Yeah, Gabe, Mr. Wheeler’s marine tank,” Dominique says. “It’s fantastic.”

Mr. Wheeler looks pleased.

“The colors are so intense,” Dominique continues. “He’s got a purple tang, Picasso triggerfish, a blue devil damselfish. They really stand out.”

“Don’t forget the copper-banded butterfly fish,” Amy adds.

“Or my green parrot wrasse,” Mr. Wheeler says. “Can you tell, Gabe, that this aquarium is my pride and joy?”

I nod.

“Kind of silly for a grown man, you think?”

I shake my head.

“It’s not silly,” Amy says.

“Every so often we have to buck up Mr. Wheeler about his hobby,” Dominique says to me. “I think whenever he’s about to spend some more money on it, he starts feeling sheepish.”

“It’s a work of art, Dad,” Amy says, “and an ongoing scientific experiment.”

“Not everyone can see it that way,” I say, thinking of a couple of my classmates.

“So?” Amy says.

“You’re exactly right, Gabe,” Mr. Wheeler says. “My wife is among those without our vision.” He laughs. “Any word on the scholarship, Dominique?”

“Not yet,” Dominique answers. “It’ll be a few more weeks before I hear.”

“Tough to wait, I bet,” Mr. Wheeler says.

“I’m trying not to think about it. I mean, I like working here, and the classes I take at the community college are good. But to be able to focus full-time on school would be so . . .” He pauses, searching for the right word. “. . . so fine. And the university’s biology programs have such a good reputation. I’d love to be there.”

You can tell how much Dominique wants it. He gazes off, eyes half-closed, like he doesn’t want to look directly at his dream because if he does he’ll jinx it.

Mr. Wheeler buys the doodad he needs for his marine tank, and then he and Amy leave. I’m ready with my plastic bags of fish, just waiting for Dad to pick me up, when the door opens again.

“Hey, Dom-Dom-Dominique,” says the big man who walks in.

“Hey, Tom-Tom-Thomas,” Dominique says. He flashes his smile. The big man doesn’t smile back. He walks directly to the display tanks and stares at them as if he’s looking for something.

“There’s not much new since last time,” Dominique tells him.

“No new purples?” the big man asks.

“Nope,” Dominique says. “But check out the black-and-white fish in the tank in the corner.”

Thomas plants himself in front of the aquarium Dominique has pointed out. For a minute, Dominique and I stand and watch the big man watch the fish.

I know this man, Thomas Doherty. It’s kind of hard to miss him if you pass him on the street. He’s big, with clumsy-looking hands, a big stomach that sticks out over his skinny legs, and brown hair that he wears in a crew cut. He always wears the same outfit—khaki pants and a white collared shirt, long-sleeved in cold weather, short-sleeved when it’s warm. Thomas is a regular at almost all of the shops in this strip. Lots of people call him Tom-Tom, because that’s what he tells you to call him—if he bothers to talk to you at all. I call him Thomas. It doesn’t feel right calling a grown man Tom-Tom.

But Thomas isn’t your average, everyday grown-up. Something is wrong with his brain, so he’s not as smart as a grown-up should be, or even as smart as a kid in sixth grade. Thomas doesn’t act very happy, but he also doesn’t act very sad—mainly he seems kind of blank. I wonder how that would feel. In some ways, I think it would be good, but I don’t know.

Dominique says that Thomas has feelings just like everyone else, he just doesn’t show them the same way. You can tell Thomas is happy, Dominique says, when he hums. I’ve heard Thomas hum, always songs that I don’t recognize, but he doesn’t smile or otherwise look cheerful when he hums. He just hums. When he’s unhappy, Dominique says, Thomas clicks his tongue against his teeth, or he blinks a lot.

Today Thomas is just staring at the fish, not humming or clicking or blinking.

“Thomas, I’ve been thinking. I’d like to do something,” Dominique says, “if it’s all right with you.”

“What, Dom-Dom? What do you want to do?” Thomas doesn’t take his eyes off the tank.

“I’d like to make you a nice aquarium that you can have at home,” Dominique says. “You can have fish living in your apartment.”

Now Thomas turns around. “That would be beautiful,” he says. “I can have colorful fish?”

“Definitely,” Dominique says.

“But I don’t have the money to pay for them,” Thomas says. “And my sister—I don’t want to ask her for the money.”

Thomas lives in one of the three-story apartment buildings down the street from the shopping strip. Domin-ique told me that Thomas eats breakfast and lunch in his apartment, but for dinner he goes to his sister’s house. He takes the city bus because she lives a few miles away.

“You don’t have to pay,” Dominique says. “Mr. Newman said you can have it for free because you sometimes go and get us lunch. You do us favors, so we’ll do you this favor.”

“I would love that favor,” Thomas says. “When will you do it for me?”

“I’ll start planning the aquarium right away,” Dominique says.

“I could help,” I offer.

“Great,” Dominique says. “And we can set it up in Thomas’s apartment next week. Does that sound okay, Thomas?”

“That sounds . . . beautiful,” Thomas says. “Especially if there are purples.”

I feel a little bad, because I think Thomas is talking about angelfish when he mentions “purples,” and the last two purple-and-white angelfish in the store are in a plastic bag coming home with me.

“On Monday,” Dominique says, “we’ll be getting in new angelfish. So you’ll have your purple fish, Thomas.”

Thomas clasps his hands together and turns to look at Dominique and me directly for the first time since he’s entered the store. “That will be beautiful,” he says. “Thank you.” He turns around to look at the tanks again, but doesn’t seem to want to stand still anymore. “Well—good luck,” he blurts out, spinning around to look at us again. “Good-bye.” He leaves the store, humming.

“‘Good luck’?” I repeat to Dominique.

He smiles, nodding. “Sure,” he says. “Thomas has seen plenty of customers come and go with fish that start out alive and end up dead. He knows how hard it is to make a really nice aquarium work. He knows we could use some luck if he’s going to get a good aquarium.”

Just then my Dad walks in the store.

“How about Tuesday for setting up Thomas’s aquarium?” Dominique asks as we’re leaving. “After school?”

Now that Dad’s here, I’m in a hurry to get my new fish home. “Tuesday is fine,” I say. “Wish me luck.”