How Much Bacteriostatic Water to Add to Peptides? Prime Peptides How Much Bacteriostatic Water to Add to Peptides? Prime Peptides CANLABS: Does BAC Water Expire? Have had for a year in fridge. : r Peptides Bacteriostatic Water Bac Water by Hospira Mountainside Medical Tagged "Sterile Water For Injection" Bottled water often carries an expiration or best by date, but pure water itself does not expire or spoil, as it lacks nutrients for bacteria growth. The date primarily concerns the plastic bottle: