This study evaluated fermented cassava pulp-based wet concentrate (WCP) as a replacement for commercial pelleted feed on growth performance, feed utilization, carcass characteristics, and water quality of climbing perch, Anabas testudineus (Bloch, 1792) during an 8-week feeding trial. A total of 360 female fish (initial body weight 1.23±0.02 g) were randomly assigned to four dietary treatments with three replicates: T1 (100% commercial pelleted feed; control), T2 (67% commercial pelleted feed + 33% WCP), T3 (33% commercial pelleted feed + 67% WCP), and T4 (100% WCP). Fish fed T3 had the highest final body weight (BW) (25.63±0.43 g), weight gain (WG) (24.40±0.43 g), specific growth rate (SGR) (5.42±0.03% day-1), and average daily gain (ADG) (0.44±0.01 g day⁻¹), significantly exceeding the control for these parameters (p < 0.05). T3 also had the lowest feed conversion ratio (FCR) (1.74±0.12) and highest feed efficiency (FE) (57.47±3.66%). In contrast, T4 had the highest feed intake (0.84±0.07 g day⁻¹), highest FCR (1.98±0.18), and lowest FE (50.51±4.10%). Carcass characteristics varied among treatments, with the highest fillet yield in T2, HSI in T4, and VSI in T3. Several water-quality parameters differed significantly, but these differences were not associated with adverse effects on growth or survival. Overall, replacing 67% of commercial pelleted feed with WCP provided the most favorable combination of growth and feed utilization under the experimental conditions. WCP therefore has potential as a partial replacement for commercial feed in A. testudineus culture, although longer-term feeding, digestibility, and economic studies are needed to confirm its applicability under commercial conditions.
