Penaeus vannamei has the potential to grow as fast as P. monodon (at up to 3 g/wk) up to 20 g (the maximum size of P. vannamei usually cultured) under intensive culture conditions (up to 150/m2). Although it will keep growing beyond 20 g, its growth may slow (particularly males) to 1 g/wk once above 20 g in weight (Wyban and Sweeny, 1991).
Under commercial conditions in Asian earthen ponds, however, typical growth rates of 1.0-1.5 g/wk (with 80-90 percent survival) are common in the high density pond system (60-150/m2) currently in use in Thailand and Indonesia. In contrast, the growth (and survival) rate of P. monodon has been declining in recent years from 1.2 to 1 g/wk (and 55 percent to 45 percent survival) over the last five years in Thailand (Chamberlain, 2003) due perhaps to disease load and/or genetic inbreeding (Table 5). Penaeus stylirostris can also grow equally fast and to a larger size than P. vannamei.