Traditionally, commercial catfish farmers use field kits to measure total ammonia nitrogen (TAN) of unfiltered pond water, but the impact of filtering and total ammonia concentration on their accuracy is unknown. Commonly used field ammonia analysis kits were evaluated by comparison to a laboratory method of 53 water samples obtained from commercial catfish farms and research ponds in Mississippi. Unfiltered samples were analyzed by two s alicylate chemical reaction-based field kit methods (M1 and M2) and compared to a filtered laboratory salicylate method (STD) read by a spectrophotometer. Total ammonia concentrations obtained from the field kits (M1 and M2) are closely correlated with the standard laboratory method up to 10 mg N/L TAN. When TAN values are higher than 10mg/L, field kit methods begin to diverge, and return either slightly lower or higher values compared to the standard method. Unfiltered water analyzed with field ammonia test kits are very reliable up to 10 mg N/L, but higher concentrations begin to lose precision and may no longer be appropriate, depending on the application.