This research examined the feasibility of Bibb lettuce roots to provide a surface for nitrifying microbes to colonize, removing ammonia from wastewater. The work is geared towards sizing a rotational plant system to act as a natural biofilter to treat wastewater from the fish farming industry, making a recirculating natural system possible. It was observed that these natural, biotic surfaces provide a more suitable area for microbes to grow compared to inert materials. Nitrification rates were quantified, and were similar in magnitude to pre-experiment estimates. In addition, a correlation between Bibb lettuce leaf mass and root surface area was calculated, which greatly simplifies the calculation necessary to size a plant filtration unit.