What is an aquatic example of what happens in commensalism?

Commensalism is a type of symbiotic relationship that exists between two different species. The other two relationship types are mutualism and parasitism. Commensalism exists when one animal benefits from the relationship and the other animal is neither hurt nor helped. A common example for commensalism also happens to be an aquatic example. That example is the relationship that exists between sharks and remoras. A remora will "hitch a ride" on a shark and gain multiple benefits. The remora will use less energy moving from spot to spot, feeds on the scraps left over from the shark's hunting, and is not likely to be bothered by other predators. The shark on hand receives no benefit from the remora, but the shark also isn't hurt by the remora.
https://kids.britannica.com/students/assembly/view/108155

https://www.nationalgeographic.org/activity/ecological-relationships/