The highest nitrogen and phosphorus removal efficiencies were observed with 5:1
(algae/sludge) culture (91.0 ± 7.0% and 93.5 ± 2.5%, respectively) within 10 days, which was 5–40% higher
and 2–4 days faster than those with other inoculation ratios. The biomass settleability was improved
with the assistance of sludge, and the 1:5 (algae/sludge) culture showed the best settleability