How many letters does the top answer for “small brilliantly colored tropical marine fishes of coral reefs” have?

The most common answer is damselfish (10 letters).

Crossword clue: small brilliantly colored tropical marine fishes of coral reefs

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

damselfish 10 letters wn-def

small brilliantly colored tropical marine fishes of coral reefs

demoiselle 10 letters wn-def

small brilliantly colored tropical marine fishes of coral reefs