Effects of carbohydrate addition frequencies on biofloc culture of Pacific white shrimp (Litopenaeus vannamei)

In Pacific white shrimp culture, adding organic carbohydrate to the pond besides feed improves water quality and shrimp performance. While the feeding frequency has significant effects on shrimp production, how often carbohydrate should be added remains unknown. This research investigated the effects of carbohydrate addition frequency of 1, 3, and 6 times per day on Pacific white shrimp production. Tapioca powder was used as carbohydrate source to maintain an input C:N ratio of 12. The same daily ration of tapioca was applied, but divided into equal portions according to the application frequency. The shrimp performance was better in carbohydrate-added systems than in a conventional system without additional carbohydrate, but the carbon retention efficiency was lower. Splitting daily dosage of carbohydrate into more frequent additions had no significant effect on Pacific white shrimp performance, and carbon and nitrogen retentions. A carbohydrate addition frequency of once per day is recommended for good performance of Pacific white shrimp in biofloc rearing systems.