This model is deal with us on a Wasserblubbersäule in use and has this 1.8m water column, which is not little. Now running for over 5 years without any problem in continuous operation !! Since a few days it should be operated in the emergency use of my aquarium to the airlift. The air pump there was a stick manufacturer took in Aquaristikbereich and has given up the ghost last week after less than 1.5 years. Schego is top in performance and durability, and by no means overpriced.