Mangagat

 

 

 

 

BASIC INFORMATION
Scientific Name : Lutjanus argentimaculatus
English Name : Mangrove Jack Snapper
Local Name : Mangagat, Managat, Maya-maya
Available Fry Sizes : Fingerlings
Marketable Sizes : 300g–800g in live, chilled or frozen form
Typical Fish Behavior : Schools and hunts. Can grow in a wide range of salinity. Fingerlings have the tendency to eat each other during the early growth stage so they should be sized every two weeks. Crowds very well, and can grow in high stocking densities
Where Grown : Marine cages and brackish water ponds and even freshwater net pens with minimal adaptation
Feeds :

Formulated snapper feed or trash fish

Feed Conversion Ratio (FCR)

:

To grow fish in brackish water ponds, FCR is 1:1.5-1.8;

In sea cages, 1:1.8-2.2

 

 

How to manage each growth stage

 

Nursery: Grows from 1-inch fry to 4-inch fingerlings in 30-45 days, feeding on ground fish or fry mash, with sizing done every two weeks.

 

Transition: Grows from 4-inch fingerlings to 80-100g juveniles in seawater ponds in about 2-3 months, feeding on trash fish or fry mash.

 

Grow-out in ponds: Grows from 4-inch fingerlings to market size in ponds in about 4 months, and up to 600g in 6-7 months. Carrying capacity of aerated ponds can reach up to 8-10mt/ha. Stocking density in brackish water ponds without aeration can be adjusted to a maximum of 3mt/ha.

 

Grow-out in marine cages and marine pens: Grows from 80g juveniles to 300-800g feeding on commercial feeds use trash fish when cheap; Grows up to 300g in about 4 months, and up to 600g in 6-7 months. Stocking density in marine cages and pens depends on water quality, parasite load, and frequency of changing nets. Carrying capacity can be 20-40kg/cu.m. depending on the site and intensity of culture.

 

*Feed Conversion Ration (FCR) measures the amount of feed needed to grow a kilo of fish. This also applies to trash fish feeding. Trash fish FCR is the kilo weight of trash fish needed to produce a kilo of fish being cultured.