Hello, I have gained this pump, because my old (10 years old) pump no longer provides the desired pressure. Background: I have a 4m deep wells and a 10-year-old pump, which then brought about 6 time bar. Now she brings not even 2 bar, thus had a New ago. I chose this Tiefbrunnenpumpe with max. 10 in wise intention that this will indeed lose over the years also at Power bar. Equipped with a long 28mm copper pipe and an adapter with 1 inch external thread, I then brought my new pump for life. Erschocken about the noise, which makes the pump, then I have the tube to below the output of the fountain's shortened and "overground" replaced by a hose to the boiler. Thus, it is whisper quiet. I have tested the pump to about 8 bar (my boiler has max. 10 bar), but as I do not need a lot of power, too. Since I had to fill my pool, which was also the opportunity to test out this page so does the pump in 4m depth of water quantity. Connect a 1/2 inch hose (40m length), the end open without pressure regulation. From about 5 bar, the pressure remained constant, the amount of water that is remarkably shoots at 5 bar in the pool. Anyone looking for a pump of similar proportions, which I can highly recommend this !!! I suspect that even Siese pump over the years lose power, but I can not tell about it only in 10 years. I run this pump with a regulated pressure of 3-4bar, thus it is not overwhelmed and will survive me hopefully.