After I wrapped myself in Prof.2224 several years with the problem of difficult-to-get tight again points between the baskets (rubber bands) and several times involuntarily put a floor under water, while Prof. 250 (2071) this problem has been solved. In this respect, the Mod. 250 is significantly better. The priming aid is a good help. Sound and performance are OK. The hoses have been enough for me. But what Eheim has meant the construction of the nozzle tube. The own mpAquarien it will not install properly. Here the solution was much more flexible with multiple rotating in share in 2224. The rigid inlet bend it does not allow that the nozzle tube on the side or the rear wall can be attached by suction cups. I speak here of the mpAquarien that behind have the passages for pump, heater, lamp, etc. in the fitted bodice. In 2224 with rotatable in share in the inlet arc, it was easy. By tinkering and inclined at a! Sucker hanging nozzle tube runs only times everything. I'll soon have finished a new passage for the nozzle arc in the upper part of the aquarium. Eheim should here return to its old design. Who exactly the problem with the sheets / nozzle tube is not relevant, gets a good device with the 2071. Addendum: 1. A mobile outlet pipes jets offered by Eheim as extra accessories. In 2224 they were there! Here is my opinion the price with cheap accessories styled down. 2. After a few days in operation, the pump is now heard, goes on day in general under Gräuschkulisse in complete silence in Room but audible. The 2224 was not to Ören.