This disclosure pertains to performance enhancing conditioning and storage solvents containing low levels of buffer and salt for reproducible and improved size exclusion chromatography (SEC). In some embodiments, the present disclosure pertains to storage solvents for protein-based size exclusion chromatography that include water, a water-miscible organic solvent, a phosphate salt, and a neutral salt. In some embodiments, the present disclosure pertains to columns for protein-based size exclusion chromatography that include porous particles and such a storage solvent.