Introduction: Aquatic contaminants can alter fish behavior before overt toxicity becomes evident, making neurobehavioral endpoints relevant for ecosystem protection and for hazard prioritization within a One Health framework. We recently developed a high-throughput visual-acoustic zebrafish larval thigmotaxis assay in which edge preference is interpreted as an anxiety-like behavioral endpoint, thereby adding spatial phenotyping beyond conventional locomotion metrics. Objective: To evaluate assay performance in a multisubstance screening challenge and determine whether it can discriminate distinct behavioral fingerprints without prior knowledge of chemical identity. Methodology: Zebrafish larvae were exposed for 1 h at 120 hpf. For each substance, 24 larvae were tested per condition, with six concentrations per substance, plus positive and negative controls. Larvae were challenged using alternating light/dark and tapping/quiet paradigms. The primary endpoint was the percentage of time spent at the edge as a proxy for anxiety-like behavior, while total distance and mean total velocity when moving were used as contextual locomotor metrics; edge distance and edge velocity were used as supportive spatial metrics. Data from 37 substances were analyzed through a standardized automated workflow. Results: Controls performed as expected and supported assay stability across runs. The chemical screening revealed heterogeneous but reproducible behavioral fingerprints. Seven substances produced weak/minimal acute responses, ten showed predominantly suppressive profiles, three predominantly activating profiles, nine showed prominent thigmotaxis-specific anxiety-like signals not explained by locomotion alone, and eight displayed mixed or stimulus-dependent patterns, including non-monotonic responses. Several substances altered edge preference while distance and velocity changed less, differently, or in the opposite direction, indicating behavioral reorganization rather than simple hypo- or hyperactivity. The multi-stimulus design was critical because some effects were evident only under specific sensory contexts. Conclusions: The multisubstance challenge supports the discriminatory capacity, robustness, and added value of the assay for high-throughput neurobehavioral screening. By capturing anxiety-like behavior through thigmotaxis and complementing it with locomotor context, the method improves phenotypic resolution for aquatic pollution assessment and offers a sensitive fish-based NAM to prioritize chemicals of concern for both environmental and human health-oriented testing strategies.