Water pollution is a serious problem affecting many parts of the world. Researchers in Japan have come up with a natural solution - custom-made ceramic rocks. Let's take a look at how plant-based pebbles are cleaning up ponds and even seawater in Nagasaki.

450,000 people visit Omura Park every year. (Omura, Nagasaki Pref.)

They come to see hard-to-find Omura Sakura cherry blossoms in spring... and massive fields of hanashobu iris flowers.

But the water...this moat was smelling like sewage.

Ceramic technology is helping to clean it up.

Workers drained the pond and added specially designed ceramic rocks. (November 20)

Hiroshi Sonoda, Omura Mayor / "Ceramic pieces are like a natural purification system."

1.4 tons of the ceramic went into the moat.

More went into the park's pond.

A difference should be noticeable by spring.

Regular quality tests until then will confirm progress.

A company called Santa Mineral developed the ceramic.
(Tamana, Kumamoto Pref.)

Ruriko Onishi, President, Santa Mineral / "The white bits are calcium, black are carbon. This is the base."

Omura Park's water is brackish and difficult to purify.

Ruriko Onishi, President, Santa Mineral / "If we can clean up Omura, we can easily clean up other polluted bodies of water."

Ceramics break down various pollutants.

Natural filtration then kicks in, and water becomes clean.

Engineers create custom ceramics for each case.

Omura needs one that can break down sewage and surfactants.

High-pH mineral water is key in the recipe.

Ruriko Onishi, President, Santa Mineral / "This water is highly alkaline, pH12. Chemicals that basic would dissolve your finger. But this is safe, you can drink it."

It's now been a month since ceramics were placed in Omura Park's moat. (December 20)

Survey says....

Worker / "The smell is gone"

City workers checked the pond as well.

Detailed analysis showed reduced levels of sulfates and other positive signs.

Koichi Furusaki, Mineral Activation Research Lab / "Oxygen saturation is 10.6 mg/L. That's a good amount."

Ceramics are also cleaning up this unique beach on Omura Bay.

Glittery sand here is made from recycled glass.

It's a hit on Instagram.

Glass was supposed to stop smelly overgrowths of algae.

But it wasn't effective.

Ruriko Onishi, President, Santa Mineral / "The nitrate to sea water mineral balance is off."

480 kg of ceramic could be answer.

This one is designed to break down nitrates from household waste water that reaches the bay.

Ruriko Onishi, President, Santa Mineral / "Ceramics will eliminate nitrates and thereby algae. Many people come here, we want the bay to be clean and beautiful."

Tourists and residents will now wait for the ceramics to their job.