I'm looking at something similar. I think the bluediamond is a copy of the hiblow. But even the hiblow is a pretty good price. The 120 moves a little over 4CFM. For my pond and from what I have learned it would probably be sufficient. There is a video on youtube that a guy had bought one of the bigmax systems on ebay and had a bad experience. But then got a hiblow septic aerator and I really like what I saw...and the ease at which it could be rebuilt. Parts are readily available also. Watch the video and you'll see a pump just like what you are looking at. Its extremely quiet also. Hope that helps some.