For Anaerobic C:N:P = 250 : 5 : 1 , for Aerobic B:N:P= 100 : 5 : 1

In general C:N:P varies from 100:10:1 and 100:5:1 for aerobic process depending upon the type of biological treatment.

Thanks

but i don't understand that what is the basic of these?

Why 250 : 5 : 1 or 100:10:1

In aerobic treatment, about 50% of the carbon are lost by anabolism as CO2, the other 50% are assimilated by anabolism in biomass.

In anaerobic treatment, there is much more carbon lost for anabolism and converted to CH4 and CO2 because anaerobic metabolism is less energetic.

The consequence is that for a same amount of carbon removed, there is much more growth in aerobic than in anaerobic treatment. This is why C/N/P ratios are different.

any good references for this part please

Nicolas Bernet thanks for your answer Will you please share any references? How can one calculate the C: N:P ratio in the wastewater?

The C:N:P ratio in the aerobic and anaerobic wastewater treatment is 300/5/1 and 100/5/1