Parameter Conventional ZWD Limit Ammonium (mg/L) 0.20-0.59 0.07-0.69 ≤3.95 Nitrite (mg/L) 0-3.2 0-3.15 ≤25.7 Nitrate (mg/L) 1.38-14.17 1.04-42.9 ≤232

Table 2: Range of ammonium, nitrite and nitrate concentration in conventional and ZWD for 90 days culture period.