When I was in the fourth grade, I begged my parents for a dog—you know how kids are. After giving numerous PowerPoint presentations on why I would be a good dog owner, they bought me a glofish instead. A glofish is not a goldfish, but a neon-colored, genetically engineered zebrafish.

Rosa at three years old

At their largest, glofish can grow to two inches, and they typically live for no more than two years. My glofish, Rosa, lived for nearly five. In an effort to understand why she survived for so long, I kept a diary of her progress.

12/29/2008 Rosa isn’t alone in the tank, at first. She lives with my sister’s fish, Crystal. Crystal and Rosa chase each other around in circles. Are they playing tag or something slightly more sinister?

3/1/2009 Rosa eats Crystal. We see the entrails caught on her tail. Like an alchemist, or a wizard, Rosa seems to absorb Crystal’s life force. Rosa swims even faster now that she has the force of two powering her tail.

9/1/2009 My sister buys another fish that looks exactly like Crystal. We don’t learn from our mistakes. She names the fish Sharky, perhaps in an effort to protect her fish from Rosa. Rosa enjoys chasing Sharky around the tank. Aerobics are quite beneficial to a fish for keeping up their level of fitness.

1/6/2010 Rosa eats Sharky. We learn our lesson the second time around and never put another fish in Rosa’s tank again. Has she consumed their life force to increase her strength and resilience? In her newfound solitude she appears to be gaining otherworldly strength. Further observation is required.

2/12/2010 Rosa swims around and around in circles. She hides behind the orange rock I bought the day I got her. I feed her twice a day. Rosa doesn’t know how small her world is.

2/13/2010 The guy at the Pet Store told me to replace 25% of Rosa’s water at a time. I don’t; I replace the entire tank of water every single time. The shock should kill her, yet it doesn’t. Why am I still surprised when Rosa’s behavior shocks me? She defies all of my scientific logic.

4/26/2010 The filter and the heater in Rosa’s tank, which keeps the 78-degree water perfectly clean, stop working. Such a cheap tank is not meant to last this long. Neither is Rosa.

6/25/2010 The water in the tank hovers at 76 degrees that summer. A glofish is only supposed to be able to survive in tropical waters: 78-82 degrees. Yet still, Rosa lives. Temperature appears to be no match for sheer willpower.

8/14/2010 The leaves of the plastic plants fall off. Rosa’s tank is green with algae and envy from those in her belly. She withstands this change because she doesn’t know how to stop swimming in circles. She withstands because she is more powerful than logical reason.

12/25/2010 Rosa’s stomach swells for no apparent reason. She becomes so fat that her cheeks bulge. My mother jokes that Sharky got Rosa pregnant. I respond that Rosa will eat any babies she had. I do not observe any tiny Rosa’s; however, Rosa’s level of aerobic prowess may have helped her consume her young prior to documentation.

1/1/2011 I put a new rock in the tank. Rosa doesn’t seem to like it. I buy a new purple plant. Rosa swims in between the leaves. She is determined to survive, even though I only feed her every other day. Does she miss her small and familiar world?

2/27/2011 Rosa swims up and down, around the rocks, and where the filter used to whir. There is too much foliage to swim in circles. She still moves and I begin to wonder why. My explorations have yielded few concrete results.

9/24/2011 The thermometer in Rosa’s tank becomes stuck at 32 degrees Fahrenheit. I pry it off with a spatula covered in dish soap, which leaves a yellow ring. Rosa doesn’t notice, even when the water dips below 73 degrees (I think)  in the winter.

1/1/2012 Rosa is three. I try to figure out how old Rosa is in fish years. Eighty? A hundred? She has lived far past her normal lifespan. More research is required.

1/15/2012 The tank turns green yet again. My mother feeds Rosa because I usually forget. The tank on the counter has become a fixture that no one notices. So has Rosa.

5/23/2012 My sister threatens to flush Rosa down the toilet, or put her in the pond behind our house, or put dish soap in the water. She doesn’t like Rosa; she’s still bitter about Crystal and Sharky.

6/17/2012 My dad glares at the tank like a stain and Rosa fixates her tiny eyes on his finger. “This tank takes up too much space!” Rosa lives anyways. She proves us all wrong in her own way.

6/23/2012 I go to camp for the summer, and I think my family forgets to feed Rosa. I leave a sticky note on her tank, “FEED HER,” and come back to a skinny fish—too slender for such a naturally voluminous presence. She struggles to swim; her treks around the tank are much slower.

8/24/2012 Rosa looks like a girl who sucks in her stomach for pictures. Her spine is a zigzag and her tiny eyes seem bigger than ever before. I feed her three times a day—I don’t forget anymore. Rosa holds on. I don’t think she remembers why she used to swim so energetically.

1/1/2013 Rosa hits four years and her tank grows even greener and she gets even tinier. I change 25% of the water at a time and put a heating pad under the tank.

5/1/2013 I win a goldfish at the county fair. I put it in Rosa’s tank. I buy a smaller tank with a working heater and filter for Rosa. Rosa dies two days later in that bowl.

5/3/2013 Rosa lived better in a green tank when I forgot to feed her, than when I took care of her in a working tank. She survived because she wanted to. Not because of what I did.

It’s strange to have a pet you never know. I call Rosa “she” because when you keep a fish in your kitchen for five years, it doesn’t feel right to say “it.” Rosa never knew me either. Did she live willfully? Or accidentally? I may never know. All I know for sure is that tiny bodies have the ability to withstand the greatest of turmoil.