Keep in mind that the Redfield Ratio applies to total Nitrogen and total Phosphorous, not just inorganic nitrate and phosphate. Total carbon as well not just vodka or vinegar for example.
Redfield Ratio: C:N:P = 106:16:1
The Redfield ratio applies to a general average of all the microbial life found in the ocean, not just bacteria.
Many bacteria can utilize organic forms of nitrogen and phosphorous when nitrate and phosphate are in low supply. Bacteria can utilize other forms of organic carbon as well.
This can make the use of the Redfield Ratio in a reef tank almost useless, but does let us know that bacteria utilize a lot more N than P to grow and reproduce.