Dear Maria, as mentioned above you may not have enough contact time with your Biocides. You might consider UV radiation with an exposure chamber sized for your required flow rates, and a bulb sized for those flow rates. Also keep in mind you may need other Pre-treatment to protect the quartz tube from fouling or particulate from eclipsing the UV rays from the bacteria. Of course these other pre-treatments would also protect your membranes on the RO as well, increasing their life and efficiency!
Dear Maria, as mentioned above you may not have enough contact time with your Biocides. You might consider UV radiation with an exposure chamber sized for your required flow rates, and a bulb sized for those flow rates. Also keep in mind you may need other Pre-treatment to protect the quartz tube from fouling or particulate from eclipsing the UV rays from the bacteria. Of course these other pre-treatments would also protect your membranes on the RO as well, increasing their life and efficiency!