Bacteriostatic Water CANLABS: Does BAC Water Expire? Have had for a year in fridge. : r Peptides GHK Cu Copper Peptide 50mg Cypress Compound Co GHK CU 50 mg Superior Chains Research Labs How to Store Bacteriostatic Water Safely Confused about whether BAC water needs refrigeration after opening? According to USP standards and Pfizer's own guidance, both room temp (2025C) and refrigeration are acceptable