Initial flush the water came out deep blue at first, then cleared. Never had other filters do this, hesitant to drink from it. Is this normal?

Hello TomW, Thank you for your question regarding the M-2-2 replacement water filters. The dark color you initially experienced is due to excess carbon particles from the carbon block inside of the filter. It is recommend to run at least 3 gallons of water through the filter prior to drinking to assist with clearing the particles and darkness of water. Although the color is not appealing to the eye, carbon is non-toxic, making the water safe to drink and will not be harmful to your health. Please reach out to us directly if you have any questions or concerns. We can be reached at 1-866-389-8827, Monday – Thursday 8am – 6pm, EST, Friday 8am – 5pm, EST. Best regards, Customer Service Team.