I initially ran a BM Curve7 on my 125g, then switched to a RO 150SSS. FOR ME, there was no comparison between the two as the RO doubled the skimmate output over the BM, and was infinitely easier to fine tune. Again, just my experience, which could be due to many factors, the least of which is the maturing of the tank...But it'll be RO for me for the foreseeable future, love the Space Saver Skimmer. Good Luck :beer: