Aeration treatment of manure that has a high total solids content (3,0 – 4,5%) has to be longer that for manure with a lower total solids content (< 1,5%) in order to stabilize the manure. If the aeration is not done during a period long enough, anaerobic activity can start during the storage period and result in odour emissions. In order to keep the manure in a stable stage during storage, secondary intermittent aeration may b necessary.