What fish are decomposers?

Fish themselves are not decomposers. Decomposers are organisms that break down dead organic matter, like plants and animals, into simpler substances.

While some fish might consume dead organic matter, they aren't the primary decomposers in an aquatic ecosystem. The main decomposers in water are:

* Bacteria: These microscopic organisms are the primary decomposers in aquatic environments. They break down dead organic matter and release nutrients back into the ecosystem.

* Fungi: Some fungi can also grow on dead organic matter in water, breaking it down.

* Invertebrates: Many invertebrates, like worms, snails, and crustaceans, play a role in breaking down organic matter.

So, while fish might consume dead organic matter as part of their diet, they don't act as primary decomposers like bacteria and fungi do.