I use the skilter 250 on a 10 gal, It was very loud, but I disconnected the venturi, and installed a wood/airstone, and air pumpt, it works much better, I got plans off the net that uses a camera film container (plastic) to put the airstone in, i don't run it after additives are added, but I let it run overnight. and it pulls out a wet coffee color liquid. the Bakpak at my LFS is 160 dollars, the skilter was $60. The bakpak may outperform the skilter to make up for the cost difference.
jack