2025 February Flash Fiction Challenge: Day 5

Some first-week reminders:

1. There is no sign-up. All you need to do is visit WritersDigest.com every day this month and click on the day's prompt.

2. You share your works in the comments section. To find the comments, just scroll all the way down to the bottom of the page, write your story right in the text box or copy/paste (whichever you prefer!), and hit submit.

3. You don't need to share your work to participate. A lot of writers aren't comfortable sharing their work here. That's totally OK! The main thing is that you're writing something every day.

4. The system will occasionally flag stories for review. There is nothing wrong with your work; our platform does it randomly. We will be going through and releasing stories periodically between the hours of 9 a.m.–5 p.m. EST Monday through Friday. If your story is flagged, just sit tight. It'll be released!

Today's prompt is to write about a purchase gone wrong.

(Note: If your story gets flagged for review, be patient—we will be releasing comments every few hours throughout the weekdays of this challenge. Our system randomly flags comments for review, so just sit tight and wait for us to set it free! If you run into any other issues with posting your story, please just send me an e-mail at mrichard@aimmedia.com with the subject line: Flash Fiction Challenge Commenting Issue.)

The Tank

The Craigslist ad said it was a rare variety of knifefish. We weren’t familiar with the species, but some back-and-forth with the owner made us confident in our purchase—our little ecosystem of mollies, gouramis, and swordtails had been doing well, and we’d even come to a truce with the cat about them. We paid with Venmo, and the fish appeared in a tank on our front step less than a week later, as promised.

It was a solid black, darker than any other species we’d ever seen, like looking into the blankness of space on a winter’s night. The way it moved was hypnotic, so smoothly it was like it was moving the water itself instead of moving through the water. We would find ourselves watching it for untold minutes in its isolation tank. Even the cat, who had learned to ignore the tanks (and their occupants), would sit and stare, stone still.

The first few weeks after we introduced him into the main tank were pretty peaceful. We would get home from work, scarf down dinner, and sit on the couch together, just watching the new fish exist.

Then the other fish started to avoid it, hiding in places they didn’t normally. The first fish showed up in the filter, then the next, almost like they were squeezing themselves into whatever place was farthest away. Then they began to disappear. We didn’t suspect the new addition at first, wondering if the cat’s sudden interest in watching the tank had turned more nefarious.

But then it grew bigger. And bigger still.

Before we could think to remove the other fish, to save them, they were gone. We didn’t even talk about it, really. We’d just come home, eat, and then sit, a captive audience, watching the fish take long, slow, circles around its enclosure.

It wasn’t until the cat went missing that we realized we should have done something much sooner. Her collar was stuck on a piece of artificial coral, the tag winking in the light as the fish moved back and forth, back and forth, waiting for its next meal.