how quiet is your Mag-12? I have a Mag-24 running and the humming is driving me CRAZY !!!!!! I have tried everything to quiet it down vice sealing it in a sound proof box.
I have the same problem with my 9.5 I think they are all like that. I can stand in front of my door going into my house and hear it out side at night. I know about all the trouble I have read about quiet one pumps. but I think I will get another one of them I never had any problems in the two years I had my last one. and I had never cleaned it that whole time.
Like Wazzel, I run a Mag12 and 18 as well. Now...the Mag12 is submerged and has been quiet since I installed it 3 years ago. The Mag18 is external and i did notice some hum. To solve this problem I placed the pump on a foam computer mouse pad that I had laying around which significantly reduced the amount of noise. And FWIW, this pump is on our 135g which is in my bedroom. HTH
