I've been doing reading on your scrubber and am looking for input on what would best suite my system. I'm thinking the L2. I'm currently feeding a cube every other day and have continued issues with nitrates and phosphates no matter the skimming, filter media of GFO and Purigen, and make shift refugium. This brings my phosphates to .05, but there are still issues with cotton candy algae, being the biggest pain of what is growing, along with some cyano in a low flow area. The nutrients in my water column are also browning my SPS. As I am running a HOB overflow, I'm thinking that running such a scrubber off of one of the Rio quiet drives as you suggest with it being suspended above the sump on the brackets, as the sump is a standard 20 long, with the gate valve. As the man who knows more about these scrubbers than anyone else, what are your thoughts towards this as a solution to this issue?