Several new glutaraldehyde- based formulations are developed with aims at improved microbial control including both planktonic and sessile bacterial control in oil and natural gas industrial water treatment. The new formulations have been demonstrated to be able to improve the biocidal efficacy of glutaraldehyde against aerobic and anaerobic bacteria in both planktonic and biofilm life styles. In addition these formulations are designed with synergistic ingredients which all have favorable environmental toxicity profiles and therefore they have a lower environmental foot print. The new glutaraldehyde based formulations also have improved product compatibility with application environments and other chemical additives in injection water fracturing fluids and production fluids compared to some commonly used biocide products in the field.