By far one of Pixar’s most adorable creations, Andrew Stanton and Lee Unkrich’s Finding Nemo is basically the definition of a comfort film. It’s story about a neurotic clownfish looking for his missing son in the vastness of the Pacific Ocean is capable of turning even the hardest of hearts into an emotional pile of goo. But, sometimes, even the softest, prettiest of stories have a darkness to them. Though Finding Nemo certainly left a more than welcome mark in the world of animated cinema, its impact on reality is a little more contentious.

Mind you, when we say Finding Nemo has a dubious legacy, we’re not talking about a handful of paranoid parents worrying about their kids finding inspiration in the titular Nemo (Alexander Gould) and getting themselves kidnaped, though that certainly crossed someone’s mind. When it comes to Finding Nemo, the issues surrounding the film’s popularity were much more palpable, at least to the marine biologists keeping track of the clownfish population in the Pacific. It turns out that love for Nemo may have spilled over to the real world, with fans of the movie desperately running to pet stores to get themselves their own clownfish for their aquarium. Add to that info the fact that clownfish are an endangered species and you can see how it becomes a problem. Furthermore, the technique used to capture the Nemos of the world has its fair share of harmful impacts on the fishes’ natural habitat, which poses a threat to the individuals still in the wild.

All of this information came into circulation shortly after Finding Nemo hit theaters. A few years later, biologists and conservationists sounded the alarm again when Nemo’s 2016 sequel, Finding Dory, was released. But was there really a cause for concern? More recently, there has been some research that points to an exaggeration factor in what became known as the “Nemo Effect.” So how much of it is true? Let’s go swimming and see what we find.

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Pixar Animation Studios was just reaching its peak in 2003, right when Finding Nemo came out. The studio had been coming from an all-winning streak starting with 1995’s Toy Story, so there was no doubt that their next movie would be a hit. And indeed it was: with a budget of $94 million, the movie made nearly $340 million at the domestic box office alone, and worldwide, it hit well over $850 million.

Finding Nemo’s plot is a simple and easily relatable one: after losing his wife and babies (or, rather, eggs) to a barracuda attack, clownfish Marlin (Albert Brooks) becomes terrified of the world around him and obsesses over keeping his one remaining son, Nemo (Alexander Gould), from all harm. One day, during a school trip (like, a school of fish, get it?), little Nemo ventures too far close to a boat and ends up being captured by a scuba diver. He’s taken to a fish tank in a dentist’s office in Sydney, Australia, and Marlin sets off on an adventure to find his missing kid. Along the way, Marlin is joined by Dory (Ellen DeGeneres), a forgetful blue tang that slowly helps him overcome his fears and introduces him to a world with wonders beyond his wildest dreams.

It all sounds so lovely that it’s even hard to imagine something negative coming out of Finding Nemo. And, yet, here we are, discussing the film’s complicated legacy. Apart from making adorable movie protagonists, clownfish are also incredibly popular among owners of marine ornamental aquariums. They represent about 43% of the industry, and though many of these fishes are bred in captivity, at least 75% of them are captured in the wild. According to Saving Nemo, a conservation fund established after Finding Nemo’s release, over a million clownfish are harvested from the wild yearly to lend their beauty to fish tanks all around the globe. These numbers saw a brief surge all the way back in 2003, when fish sellers noticed a spike in the demand for clownfish. “I think it was a big surprise, because the message from the film was a very good one about conservation”, Karen Burke da Silva, a biodiversity professor at the Flinders University, in Australia, and one of the founders of Saving Nemo, told the Washington Post.

This heightened interest in clownfish leads to a massive decrease in population numbers, and not just because the fish are being taken away from the ocean. As shown in Finding Nemo, clownfish are native to coral reefs in the Pacific Ocean. Unlike what is shown in the movie, however, fishing them is hardly as simple as putting them into a small netted bag. To catch a clownfish, fishermen tend to first spray them with cyanide. The substance acts as an anesthetic, knocking out the fish and making them easy to catch even with one’s own bare hands. This not only increases the chances of the fish dying in transport or developing an illness later in life, but it also has a lasting impact on the ecosystem.

According to the conservationist NGO WWF, the substance kills the polyps and algae that live in coral reefs, turning these rich, colorful parts of the ocean into virtual deserts. Without the algae, the coral loses its color, or, in other words, becomes “bleached.” This process inevitably leads to death, which, in turn, eliminates the environment that clownfish and other species depend on for survival. Though cyanide fishing is illegal in most of the world, the practice is still very common due to the high demand for reef fish in both the aquarium and the food industries.

Dubbed the Nemo Effect, this alleged increase in the demand for clownfish was such a big deal that, when Finding Dory came along, marine life researchers and conservationists sounded the alarm once again. Their fear was that aquarium owners would suddenly flood the market with requests for blue tangs. Since this species cannot be bred in captivity, there was a general concern over the impact that its massive fishing would have on the environment. Thankfully, nothing of the sort happened.

As a matter of fact, researchers from the University of Oxford who were looking into the Nemo Effect found that it might have been largely exaggerated and that it’s even hard to find out where these claims first started. Led by zoologist Diogo Veríssimo, the researchers involved in the study “looked at data on online search patterns, from the Google Trends platform, fish purchase data from a major US importer of ornamental fish and visitation data from 20 Aquaria across the US.” They found no evidence that there was a spike in the demand for clownfish, but they did notice a surge in searches about clownfish and aquarium visitations. So, as it turns out, Nemo and Co. might have had a positive impact on the general awareness of endangered fish species and the threats they face. This, however, doesn’t mean you shouldn’t be wary of where you get your pretty clownfish from.