The WellWatcher Flux multizonal reservoir monitoring system provides continuous sandface monitoring across one or multiple zones. The high-resolution distributed temperature sensors allow for better detection of subtle temperature changes, thus enabling real-time updates to production and injection profiles, permeability and skin changes, indications of water breakthrough and fines movement, and detection of out-of-zone injection. For reservoirs producing high-rate gas, the WellWatcher Flux system detects the variations associated with water breakthrough, as well as the more localized increases that can indicate hot spots that could lead to screen erosion. Based on this information, the operator can then take immediate action using surface or downhole chokes to reduce the gas flow rate. For water injection applications, the WellWatcher Flux system delivers real-time pressure and temperature measurements across each zone, enabling operators to detect and avoid out-of-zone injection or overpressuring zones. Creating an accurate injection pressure matrix early in the process, not only helps prevent loss of containment by ensuring caprock integrity. It also enables more efficient pressure support for producers, saving the customer time and optimizing reservoir drainage. Many high-rate oil producing wells suffer from fines migration if exposed to high drawdown, which potentially results in hotspots that can permanently damage the sand control apparatus. The WellWatcher Flux system can derive a productivity index along the wellbore during monitoring, enabling operators to produce at the highest possible rate while reducing the risk of fines migration. The WellWatcher Flux system brings value to a single well or an entire field when strategically placed across the reservoir. Operators can now detect changes earlier than ever before, improving well management and optimizing reservoir drainage.