Approximately 40 cubic yards, I fill it in 7 hours. Anaerobic bacteria cause the smell, the purpose of this drum is to create a suitable environment for aerobic bacteria so no smell. Output is CO2, ammonia and water vapor. We will collect water initially approximately 200 gallons a day. Want to feed the rest to nitrification bacteria in a sulphuric medium to get some ammonium nitrate. But it is a project for the future need to stack some sats first :)