
You may be familiar with oysters as the delicious seafood best eaten raw (or as ice cream) and served in months ending in “r,” but did you also know the little guys have impressive filtering skills that can clean even the dirtiest water?
Eating its fill of plankton and other particles floating around, a fully grown oyster can filter more than 50 gallons (189 liters) of seawater in one day. After seeing a few videos demonstrating this cleaning ability, some Japanese netizens started to question just how appetizing this made the once delicious-looking oyster.
In the video posted by a U.S. environmental advocacy group, two tanks of dirty water are placed right next to each other with the only difference being that one is filled with oysters. About two hours pass in the short time-lapse video and the oyster-filled tank looks practically clear by the end.
As you can see it dramatically displayed in the video above, the humble oyster does a pretty amazing job of keeping bodies of water clean (and arguably better than NASA-designed water bottles). And for most of history, natural oyster beds have been keeping water clean all over the world. Check out another video showing a group of oysters at work.
Unfortunately over-harvesting, disease and pollution have taken their toll on oysters all over the world, leaving nature’s water filter at less than one percent of its historical population. And after seeing these videos, Japanese netizens came to realize just how important the oyster is to marine ecosystems. But after pondering the oyster’s role in keeping our oceans clean, viewers began to worry about a different pressing issue: isn’t it a little disgusting to be eating something that has been sucking in all that junk from the ocean?
▼Who cares if oysters have been filter waste from the ocean if you can grill them wrapped in delicious bacon?

A lot of commenters pointed out that while this was great news for cleaning up our oceans, this was bad news for any oyster lover who would be turned off the shellfish after seeing videos of them filtering water so effectively. Some concerned oyster lovers said they would be making sure from now on exactly where their next round of delicious oysters come from and whether or not they were living in polluted waters. And a few commented that eating oysters was no more disgusting then eating liver as it is an organ in an animal’s body that also acts as a filter.
At the end of the day, with the dismal state of some of the world’s water, such as Tokyo Bay’s unfortunate tendency to turn red in the summer months, hopefully our friend the oyster can help us in getting that natural balance back. In the mean time, double-check where your oyster is coming from and say thanks to the hardworking shellfish before you douse him in lemon and sherry vinegar sauce.
Feature Image: YouTube (Florida Oceanographic)
Source: Karapia, National Oceanic Atmospheric Administration

How are you supposed to wash a Japanese futon duvet at the laundromat?
Face lettuce appears in Japan, with the face of Death Note’s Light Yagami, but why?
Family Mart’s new Famima flagship in Tokyo has a hidden gem that most visitors miss
Studio Ghibli adds new Ponyo glassware to its anime lineup for summer
Tokyo subway installing new ticket gates that don’t accept payment through Suica or other IC cards
How are you supposed to wash a Japanese futon duvet at the laundromat?
Face lettuce appears in Japan, with the face of Death Note’s Light Yagami, but why?
Family Mart’s new Famima flagship in Tokyo has a hidden gem that most visitors miss
Studio Ghibli adds new Ponyo glassware to its anime lineup for summer
Tokyo subway installing new ticket gates that don’t accept payment through Suica or other IC cards
Japanese Shinkansen becomes an overnight hotel for three nights this summer
Starbucks Japan releases a miniature display rack so you can create your very own store at home
Pokémon’s cozy city builder game inspires Cozy (Corner) cakes in Japan! [Photos]
Universal Studios Japan requiring consent form for adults-only horror attraction
Japanese Coo-Che becomes a viral sensation, and everyone wants a taste
New Shinkansen luggage drop-off system begins in Japan, making train travel even easier
99-year-old woman rescued while attempting to climb Mt. Fuji
Japanese convenience store releases Japanese convenience store-flavor fried chicken
Which country’s foreign tourists spend the most money per-person in Japan? Hint: Not the U..S. or China
Japan now has human refrigerators inspired by Japanese vending machines
Giant Evangelion Spear of Longinus to be installed at Japanese train station with Eva art trains
Studio Ghibli releases anime T-shirts that pay homage to one of Hayao Miyazaki’s most personal films
Studio Ghibli has a new anime out, and there’s only one place in the world where you can see it
Salomon releases Japan-exclusive Mt. Fuji hiking gear that doubles as an amazing souvenir
Hatsune Miku collaborates with Hokusai’s art in new Vocaloid ukiyo-e illustration series [Pics]
Japan triples departure tax, foreign tourists and locals now must pay more to leave country
Family Mart opens new “Famima” flagship store in Tokyo that’s like a tourist attraction
Sanrio Character Poll announces winners, Hello Kitty absent from top 10 in many countries
Japan announces sudden 400-percent increase in visa fees for foreigners entering the country
Japan’s human washing machines will go on sale to general public, demos to be held in Tokyo
Starbucks Japan releases new drinkware and goods for Valentine’s Day
Starbucks Japan releases new sakura goods and drinkware for cherry blossom season 2026
Japan’s newest Shinkansen has no seats…or passengers [Video]
Japanese ninja certification exam attracts 131 candidates from Japan and abroad
Put sesame oil in your coffee? Japanese maker says it’s the best way to start your day【Taste test】
Japanese Shinkansen becomes an overnight hotel for three nights this summer
Starbucks Japan releases a miniature display rack so you can create your very own store at home
Pokémon’s cozy city builder game inspires Cozy (Corner) cakes in Japan! [Photos]
Universal Studios Japan requiring consent form for adults-only horror attraction
Japanese Coo-Che becomes a viral sensation, and everyone wants a taste
Giant Evangelion Spear of Longinus to be installed at Japanese train station with Eva art trains
Which country’s foreign tourists spend the most money per-person in Japan? Hint: Not the U..S. or China
Why is Taco Bell failing in Japan, even as the country falls in love with tacos?
Starbucks Japan adds a new summer Frappuccino to the menu, but is it as refreshing as it looks?
Kodama Shinkansen trains on popular Japan route get a whole new look this winter
Dance with demons in Kyoto at this Edo-period Japanese Halloween festival
Hatsune Miku collaborates with Hokusai’s art in new Vocaloid ukiyo-e illustration series [Pics]
New Shinkansen luggage drop-off system begins in Japan, making train travel even easier
Studio Ghibli releases Japanese curry shirts in honour of anime about the studio’s staff