I searched the two filters for the past hour and its great but i'm looking for anyone w/ personal experience on either filter up to date....i would like it to be quieter than my air pump that i have puttin air into my 30 gal and 10 gal, b/c i cant hear 3 aquaclears over my air pump. Second, the search says Eheim is the best, but a lot of people were complaining about media that you cant or is difficult to clean as opposed to trays that the xp3 comes w/?? Can anyways explain this? I also read a problem w/ xp3's that they have air leaks or something that requires a rebuild kit of seals? I dont want to worry about rebuilding a brand new filter that i'm spending $100 on. Also the rena is cheaper by 40 bux at big als....yet it cycles 100gph more than the ehiem and will handle a 25 gal larger tank. Overall i'm looking for something that will not give me any problems, quiet, but efficient enough to handle the new 125 gal i'm getting. Let me know what you all think. Thanks