Marine Animals and Predators
There are many different relationships between plants and animals in the ocean. The biggest one of them all is probably the preadtor-prey relationship. Marine animals need food, so they prey on smaller or weaker animals to get it. Other relationships can benefit both animals, like when an animal uses another for comaflague, and the other uses it's left-over food for a food source.
This diplays many relationships between marine animals.
Fish are friends. Not food.
Many fish get along. But some can get carried away and eat one anthoer.
These fish live together and use eachother to their benefit.