The increasing frequency of harmful algal blooms (HABs) driven by climate change has raised concerns regarding the detection of toxins such as okadaic acid (OA), cylindrospermopsin (CY), microcystins (MC), and anatoxin (ANA) in environmental samples. These toxins pose significant risks to human health, ecosystem, and water safety. This study presents AquaQuanta, a portable multiplex photonic aptasensor based on cholesteric liquid crystal network (CLCN) technology for real-time, simultaneous detection of these four major toxins. The sensor incorporates four distinct aptamer-functionalized CLCN biosensor chips, each tailored to detect a specific toxin. The device operates as a battery-free, label-free, and fully portable platform, enabling easy and rapid toxin detection without the need for complex instrumentation. The sensor demonstrated good selectivity and sensitivity, with clear colorimetric shifts observable to the naked eye, corresponding to toxin concentration changes. The AquaQuanta aptasensor offers a cost-effective, practical solution for environmental monitoring, especially in remote areas where traditional laboratory facilities are not accessible. Its high portability and ease of use make it a promising tool for global water safety and toxin monitoring.