Aquaponics is a holistic technology which integrates fish farming and hydroponic vegetables production with water continuously circulating throughout the system. The objective of our research was to determine and maintain optimal water quality parameters across a DWC aquaponics system to achieve fish and vegetable yields that exceed or are comparable to those of individual traditional hydroponic system for the same quantity of water and nutrients consumed. A completely randomized des ign was established with Tilapia and green leaf lettuce each with three replications for both an aquaponics and hydroponic systems. In the aquaponics system , 62 Tilapia fingerlings (7.5 to 10 cm) were stocked in each 750 L fish tank. Both systems were based on a nearly 950 L capacity plastic rectangular grow beds (1.2 m wide , 2.4 m long, and 30 cm deep) . There were 4 floating rafts with 28 holes for grow cubes each totaling about 3 m2 of grow space per bed. Both the aquaponics and hydroponics utilized Rockwool cubes as a growing media. Green Muir pelleted lettuce seed was sown into the rafts on a weekly rotation and harvested at around 35 to 40 days due to their close planting density, short growth period and frequent harvest. Lettuce growth and yield parameters plant height, photosynthesis, and chlorophyll (as a measure of N uptake using SPAD meter), biomass yield and protein content, and nutrient and heavy metal contents were measured. R esults showed that lettuce grown under aquaponics had better leaf geometry and significantly higher photosynthetic rates and increased chlorophyll contents than that of the lettuce grown under hydroponic system . Of o f the 13 harvests that have been done so far, aquaponics leafy biomass of lettuce totaling of 33.1 tons/ha and root biomass totaling of 6.7 tons/ha, with a shoot: root of 4.9 . In co ntrast, hydroponics leafy biomass of lettuce totaled 21.3 tons/ha and root biomass totaled 4.6 tons/ha, with a shoot: root 4.6 . In other words, aquaponics had a significantly higher (by 7%) leafy green biomass production, as compared with the hydroponic system. While both macro- (C, N, P, Ca, K, Mg, and S) and micronutrient (Fe, Mn, Zn, Cu, B, Mo, and Si) contents were higher, the heavy metals contents (Al, Ni, Cr, and pb) were lower in the leaf biomass of lettuce grown in the aquaponics, with respect to lettuce grown in conventional hydroponic system. The water quality parameters such as pH, EC, redox, ammonia, nitrate, phosphorus, total dissolved solids, BOD and COD measured on a weekly basis were much steadier and more balanced under aquaponics when compared with hydroponic system.