Ponds
Earthen ponds (typically ranging from 1 000 to 10 000 m2) are of simple design and are sited adjacent to or near river tributaries. Producers aerate the ponds and exchange water for several hours daily during the culture period by tidal exchange and pumping; this reduces muddy off-flavour and produces whiter flesh. Despite recommendations from government extension agencies to stock 20-40 fish/m2, intensive monoculture ponds are usually stocked at 40-60/m2, with some grow-out farmers stocking even higher. Yields reach 250-300 tonnes/ha/crop, exceptionally reaching 500 tonnes/ha/crop in ponds. Striped catfish reach 1.0-1.5 kg after 6 months or less, depending on the size of fingerlings stocked. Today (2010) few striped catfish monoculture grow-out producers can be described as ‘small-scale’ because the minimum harvest from a single pond is usually 50 tonnes or more.