The abiliy dowse IV isn't detecting schools of fish at grade 3 areas. It works correctly at other areas so i assume the schools of fish of these areas that are bugged/missing, not the ability.

Platform: PC
ISP: BrTurbo
Type of Internet Connection: ADSL
Internet Connection Speed: 2MB
Date & Time: 05/01 10PM
Frequency: always
Character Name: Lienn Deleene
Race: Miqo'te SoS F
World: Istory
Class/Skill Rank: FSH 23
Physical Level: 50
Area and Coordinates: -
Party or Solo: solo
NPC Name: -
Monster Name: -
In-Game Time: -
Steps:
1: Enter a Grade 3 area (Horizon, Bloodshore...didn't try at tranquil).
2: Use Dowse III or higher (i used Dowse IV).
3: Even though its a valid area for the ability, it will say that there's no schools of fish grade 4 or lower in that area (grade 4 because my dowse is Dowse IV)