I have an eheim 1250 and when reading about the aquaxtreme 50z-dc12 I nearly fell of my seat when people were describing the 1250 as silent.
Im not just being uptight about a little bit of noise. In the past I have put up with more noise than I ought to from my pc. I know this since I dont need a doctor to tell me I have the equivalent of tendonitis in my ear.
I dont blame it on my eheim 1250 it was probably in the largest part due to a my first case I bought the "tornado" a standard case modded with extra 80mm fans by none other than overclockers.co.uk.
It was quite honestly not fit for purpose in its standard guise, but I ran the fans at 5v; but over time my ear has become very sensitive to background noise. This results in a high pitched tone, much like u get after u've listened to some REALLY loud music for too long from a public loudspeaker. The only time it really disappears is when I get away from my PC, but any loud noise can set it off.
I generally use headphones now when near my PC, since even then background hum of my monitor gets my ear going.
So I have my pc in a "cupboard" which is actually a closet off my room, in a P180, so I can leave it running p2p.
I planned to mount my eheim 1250 on some purpose made rubber grommets I bolted to the inside of my case but the pump vibration made this absolutely counter to the reason I bought a new case, the P180.
Currently its suspended via string from my case which is the next best thing to physically holding it. Only problem with that is I cant shut my case side. Ive run the pump for a couple of years on neoprene and recently plumped up a pillow and the vibrations are turned into noise even resting on that, so Im a bit weary of "space age" material fixing it.
Thats why I was asking about different pumps.
If what Ive heard from a few people is true, that the eheim 1250 is silent then I must have an out of balance drive shaft.
The only option of closing the case panel if I run a pump with similar dimentions to the 1250 (11cm tall including barb) is to buy a 90' barb to join pump output to gpu wb input.