There are 100 different types of fish you can find in the surrounding waters. Each fish is a member of 4 different tiers that are all worth a different amount of money when sold to the Fishmonger. Those tiers are Common, Rare, Exotic and Legendary.
The fishing contest is automatically ran 6 different times every day and lasts for 5 minutes. To win the contest you must catch the most fish within that time. The top 5 players at the end of the round will be rewarded with a set amount of emeralds that can be spent at the NPC shops.