The ocean is vast and full of creatures that generate mess, but there are also plenty of creatures that spend their time making sure that the ocean is clean and healthy.
These incredible creatures form a symbiotic relationship with other animals in the ocean to clean it, benefiting both animals.
Let’s take a closer look at these animals.
What are cleaner fish and why are they important?
Cleaner fish and other cleaning creatures are vital to the balance of life in the ocean. By removing parasites, dead skin, and bits of leftover food, they protect other marine animals from disease and discomfort. Without them, harmful parasites would quickly spread through populations of fish, leading to weaker ecosystems and declining reef health.
These hardworking species also support biodiversity by keeping reefs thriving and allowing fish to stay strong. Their presence reminds us that the ocean is an interconnected system, where every animal — big or small — plays its part. Protecting these cleaners and their habitats is just one reason why ocean conservation is so important.
What is symbiosis?
Symbiosis is when two different species live closely together and interact in a way that benefits at least one of them. In some cases, both partners benefit. This is known as mutualism. A classic example is the cleaning behaviour found on coral reefs, where cleaner shrimp or wrasse eat parasites off larger fish. The cleaner gets a meal while the larger fish enjoys better health.
In other cases, one species benefits and the other is unaffected. This is called commensalism. An example is remoras, which attach themselves to sharks to feed on scraps without harming or helping the shark.
These interactions are a wonderful way to show children how animals can work together in nature, turning a simple meal into a lesson in cooperation.
Creatures that clean the ocean
There are many remarkable marine animals that take on the role of ocean cleaners. Each has a unique way of keeping their environment clean and balanced.
Cleaner shrimp
Cleaner shrimp are tiny but mighty. They set up special “cleaning stations” on the reef where larger fish line up to be groomed. With delicate precision, the shrimp remove parasites, dead tissue, and food scraps. Remarkably, they even climb inside the mouths and gills of big fish to do their job, without being eaten.
You can meet the Cleaner Shrimp at Tynemouth Aquarium. To learn more before your visit, visit our full blog: Cleaner Shrimp: The Cleaners of the Sea!
Cleaner wrasse
Perhaps the most famous cleaner fish of all, the cleaner wrasse is often found darting around coral reefs. These small, brightly coloured fish remove parasites from larger fish, sometimes even swimming inside their mouths. This behaviour is a perfect example of mutualism: the wrasse gains a reliable food source while the larger fish enjoys better health.
Remoras
Often called “The Shark Cleaners”, remoras have a special suction disc on their heads that allows them to attach to sharks, rays, and other large marine animals. They feed on parasites and leftover scraps, reducing irritation for their host. This relationship is an example of commensalism, as the remora benefits while the shark is unaffected.
Despite their close connection, sharks do not eat cleaner fish, recognising them as helpful companions rather than prey.
Juvenile angelfish and butterflyfish
Some species take up cleaning roles when they are young. Juvenile angelfish remove parasites and mucus from other fish, engaging in a mutualistic relationship. Certain butterflyfish species also perform cleaning duties early in life. As these fish mature, they often change their diet, showing how roles in the ocean can shift as animals grow.
Sea cucumbers
Sea cucumbers act like nature’s vacuum cleaners, feeding on sand, detritus, and decaying matter on the ocean floor. As they digest and recycle sediment, they clean the seabed and release nutrients back into the ecosystem. This process keeps the seafloor healthy and supports the growth of other life, like coral reefs.
Sea sponges
Sea sponges are simple but powerful cleaners. They pump thousands of litres of water through their bodies each day, filtering out bacteria, plankton, and organic particles. By keeping seawater clear, they improve water quality and provide shelter for many reef animals.
Parrotfish
Parrotfish use their strong beak-like mouths to scrape algae off coral reefs. This prevents algae from smothering coral and allows reefs to grow strong. They also produce sand by grinding up coral and passing it through their digestive system, helping to form the beautiful white beaches found in the tropics.
From tiny shrimp to colourful wrasse and even parrotfish that create sand, cleaner species are essential to the health of our oceans. They help reefs stay strong, reduce the spread of disease, and recycle nutrients in clever and surprising ways.
At Tynemouth Aquarium, you can meet many of these amazing ocean cleaners for yourself. Book your tickets now!