When Sharanya Prasad saw a photo of a small betta fish languishing in a cup full of dirty water at a Walmart store, she knew she couldn’t stay silent.

Prasad's friend Julie Janovksy took the photo in 2014 at a store in Woodstock, Virginia, but a quick Google search reveals several news articles and numerous complaints over the past few years about the condition of the fish at various Walmart locations across the country, citing filthy water, too-small tanks or containers and diseased or dead fish on the shelves.

Julie Janovsky/Care2

Prasad, manager of campaign strategy at social networking site Care2, launched a petition asking Walmart to “immediately improve the living conditions of pet fish in all Walmart stores.” Specifically, the petition demands “full tanks with filters and proper care” for the animals.

Walmart said in a statement to The Huffington Post that if customers feel something seems wrong with the fish at any store, they should bring it to the attention of the manager:

“We recognize and appreciate our obligation in the care and feeding of our live fish. We have processes in our stores that allow for the proper care of all betta fish by our associates. Like anything else in our store, if something doesn’t meet our customers’ expectation, we hope they’ll bring it to the attention of store management. When we are made aware of such an issue, we take immediate action.”

As of early Friday afternoon, the petition was nearing its goal of 160,000 signatures, but Prasad says she’s seen no evidence that anything has changed since 2014.

When people think of animal welfare, they often overlook fish, and Prasad says that’s a huge mistake.

“A lot of people don’t think the same way about fish they do about puppies and kittens,” Prasad told HuffPost. “But they are sentient animals that feel pain.”

Jonathon Balcombe, author of the recently published What A Fish Knows, a book on the cognitive abilities of fish, agrees.

“We still labor under the delusion that [fish] don’t feel pain,” he told HuffPost. “We don’t relate to them, so we think they don’t matter.”

An oft-cited 2013 study claimed fish likely don’t feel pain “as humans do,” but that study received numerous rebuttals from other scientists who disagree.

If people paid attention to the growing body of research about fishes’ mental capabilities, their feelings about fish might change, Balcombe said.

“Each one is a unique individual,” he said. “They recognize each other, they can recognize our faces … They matter, they count, and we need to reflect harder on our interactions with fishes and adjust those accordingly.”

Fish sold as pets, and betta fish in particular, suffer from people simply not understanding them.

Though people often think of fish as mentally vacant, experts say captive fish benefit greatly from mental stimulation and enrichment.

“The perfect example of that is to think of a goldfish in a fish bowl,” Balcombe said. “That’s not the ideal situation for the fish because there is nothing in that environment to enrich their experience.”

Robert Stebler via Getty Images Your betta deserves better than this.

But Prasad is optimistic that attitudes towards fish are evolving, even though it can sometimes seem like people just don’t care about their well-being.

“The fact that hundreds of thousands of people have signed this petition shows that’s not the case,” she said.