Milkfish (Chanos chanos) Farming: A Production Guide

Milkfish (Chanos chanos) is a hardy, low-trophic foodfish farmed in brackish ponds, pens, and cages across Southeast Asia, traditionally raised on natural algal mats.

Overview

Milkfish (Chanos chanos) is the sole living species of the family Chanidae and one of the most important farmed food fish in Southeast Asia. It is extremely euryhaline, tolerating a wide range of salinity, and feeds low on the food chain as a herbivore and detritivore. These traits make it hardy and inexpensive to grow. Indonesia, the Philippines, and Taiwan are the leading producers; in 2005 about 595,000 tonnes were harvested, and milkfish accounts for a large share of Southeast Asian pond aquaculture.

Culture systems

Milkfish are grown in three main systems: shallow brackish-water ponds, pens in bays and lakes, and cages in coastal waters. Traditional pond culture relies on shallow water, often around 30-40 cm deep, where fish graze on a natural microbenthic algal mat known as 'lab-lab' (also 'lumut') that develops on the fertilized pond bottom. Pen culture was introduced in the late 1970s, and marine cage culture, including in dedicated mariculture parks in the Philippines, has expanded production beyond traditional ponds.

Seed supply and hatchery

Milkfish farming historically depended on wild-caught fry collected from coastal waters. Replacing wild fry with hatchery production has been a major focus, and hatchery technology is now established: in Taiwan, hatcheries produced more than 116 million fry as early as 1991. Hatcheries use sea cages, large saline ponds, or concrete tanks to spawn broodstock and rear larvae through nursery stages to fingerlings.

Pond preparation and grow-out

• Nursery compartments are integrated with grow-out ponds, often making up a quarter to a third of the pond area
• Pond bottoms are fertilized to grow the lab-lab algal mat as natural food
• Fry are acclimated and stocked into nursery sections at high density, then thinned for grow-out
• Supplementary feeds are added in semi-intensive and intensive systems to raise yields
• Traditional brackish ponds yield on the order of hundreds of kilograms per hectare per year, with higher yields under intensification

Growth and harvest

Milkfish grow relatively quickly and are typically harvested at market sizes of roughly 20-40 cm in length and about 250-500 g in weight. Ponds are usually harvested by draining and netting, while pens and cages are seined or lifted. Because milkfish are hardy and feed low on the food chain, they are well suited to low-cost, extensive and semi-intensive production.