It would be good to know ...
Published by Marina Vasiljevic, Sole Proprietor at M ENGINEERING ZONE
It would be good to know what package is used in bio trickling filter as well as is it operating full capacity.
I have found some suggestions from Lantec company based on results of their pilot plant (with patented media) for wastewater pumping station in USA
here is the chapter
"When the biofilter was started up in May 1999, the H2S removal efficiency increased gradually as biofilm developed on the media, but it remained below 45%. A commercial lawn-fertilizer dispenser was connected to the make-up water line to add ammonium phosphate and urea as micronutrients. After that, the H2S removal efficiency rose to over 90% within a few days. Since then, the removal has been consistently over 90%, even though the inlet H2S level varied as much as 400% within the same day"
the link is here
http://www.lantecp.com/products/hd-q-pac/biotricklingarticle
Looking forward receiving more data on your biotrickling filter media