What kind of system are you ...
Published by Mark Milne, Wastewater Superintendent
What kind of system are you running? Bio ammonia removal (nitrification) will use alkalinity and lower pH. Low alkalinity will inhibit ammonia removal. Many things can be used to increase alkalinity. I would also look up the Modified Ludzack - Ettinger (MLE) process, it can help recover about 2/3 of the alkalinity through denitrification.
As for chemicals to increase alkalinity, lime works but makes more sludge, sodium bicarbonate is nice to handle but takes a lot more, Magnesium products can make struvite, and NaOH is expensive.
Hope this hepls,
Mark