Treatment fluids for use in fluid loss control, diversion, and plugging operations and methods of use are disclosed. The treatment fluids contain a degradable particular langbeinite material that temporarily creates a physical barrier to fluid flow before degrading over time with little to no effect on the environment. This degradable additive can be combined with other traditional downhole additives such as surfactants, viscosifying agents, biocides and the like, allowing for a wide variety of applications in hydrocarbon reservoirs.