Hello, I have a tank with an UGF and a HOB at the moment. I want to convert my UGF to a RUGF but am unsure iF 2 Penguin 550's will do the trick. My main thing is do they work in a reverse mode or not. IF they do how do I set them up for reverse mode. I have read alot that the 1140 is good but also does that have a reverse. My main worry about the 1140 is that it may cause to much current for my tank as it is only a 20g. Any ideas would be great. Thanks.