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Methods are needed for treating aquaculture wastewater. The goal is to improve water quality sufficiently for it to be recycled to production ponds. One method is to use floating vegetation in treatment tanks. Alternatively, the floating vegetation could be grown directly on the production ponds. A study with floating vegetated mats for improving aquaculture wastewater quality is being conducted at the Univ. of GA Aquaculture Unit in Tifton, GA. The objective is to determine amount of biomass produced, nutrients removed, and quality of the treated wastewater. Wastewater from fish-production ponds is pumped into sets of 1285 L aquaculture tanks. There are three tanks in series in each treatment set, and three replicate sets per vegetative species. Each tank contains a floating platform (1 m2) for growth of vegetation. During a prototype test of wetland, horticultural, and agronomic plants, it was determined that cattail, iris, or soft rush were suitable for growing in aquaculture wastewater. The treatments are three-tank sets of cattail, iris, soft rush, or a control (no plants). The water is circulated every three weeks such that tank 1 receives water from the fish pond, tank 2 receives water from tank 1, tank 3 receives water from tank 2, and tank 3 is drained into a nearby storage pond. Water samples for analyses are collected from each tank prior to transfer to the next tank. Plant biomass is harvested as needed. Measurements are made of total biomass per tank and nutrient content (N, P, and K) of the plant tissue. Water quality measurements include N, P, K, BOD, chlorophyll, O2, turbidity, and pH. This paper presents partial results of the three-year study which started in May 2009.