<p>CAPM₅, a newly developed degradable sinking agent, shows promise in forming effective barriers to control fracture height without damaging the reservoir. Laboratory experiments were conducted to evaluate the plugging and removal abilities of CAPM₅. These experiments simulated the deployment and compaction of the sinking agent within fractures and tested the conductivity of closed fractures post-degradation and post-acid etching. The results indicate that CAPM₅ forms effective barriers with significant pressure-bearing capacities in both initial and stable states. Initial barriers in steel cores showed a decrease in pressure-bearing capacity with increasing fracture width, whereas stable barriers in carbonate cores exhibited increased pressure-bearing capacity with wider fractures. According to the net pressure during the acid fracturing process of the carbonate reservoir in the Gaoshiti gas field, which is approximately 5-7MPa, effective barrier is predicted to form at a fracture width of 2-4 mm at the fracture’s bottom. Furthermore, fractures subjected to residual acid etching displayed a significant decrease in conductivity with increasing closure stress, however a minimal level of conductivity remained. Non-etched fractures showed significantly lower conductivity compared to etched ones under the same stress conditions, and high closure stress resulted in almost complete loss of conductivity, effectively isolating bottom water and preventing high water production. In conclusion, the degradable sinking agent CAPM₅ demonstrates substantial pressure-bearing capacity and effective barrier formation during acid fracturing operations. Following degradation, CAPM₅ minimizes reservoir damage and effectively isolates bottom water, offering a promising solution for managing deep carbonate reservoirs.</p>