“Milkfish might not be the cheapest fish bait, but it is surely one of the best baits for catching tuna”
– Japanese and Sri Lankan buyers once said.

As we all know, there are some different options of bait fish for long-line fishing, and milkfish is considered as one of the best bait fish in the world for catching pelagic fish, especially tuna.
 
Historically, milkfish has been used for long-line fishing bait for many years, since 1980s.
Milkfish has been widely used for long-line fishing bait in many countries, such as in Japan, Taiwan, Korea, Sri Lanka, Indonesia, Spain, South Africa, Peru, etc.
 
Milkfish is one of the best bait fish in the world for these following reasons:

Strength Milkfish has long-lasting muscle tissue when it is put in the water.
Milkfish lasts for many hours or even days in the water when in use for long-line fishing.
In comparison, some other bait fish have weaker muscle tissue, so they will be gone after a few hours in the water.
Shining Scales/Skin Milkfish has silver and shining fish scales/skin.
In the day, milkfish can reflect the sunlight. While in the dark, milkfish can be also noticeable.
This makes milkfish attract various fish in the sea, including tuna.
High Catch-rate Compared to other fish baits, using milkfish as bait has a big possibility to catch pelagic fish, especially tuna.
This is why some scientific studies mention that milkfish is one of the most effective baits in the world.
Competitive Price With many advantages, particularly high-catch rate, milkfish price is considerably competitive compared to other bait fish.