I have one. rangermonroe@poetworld.net is my e mail. I have a diagram to plumb ir, but I cannot post it here as it is too large. I will happily send it to you via e mail. I like mine, but it is the only one that I have ownde, so my opinion is not " fair and ballanced".
I used one for a few months to cure some rock and didn't like it. I have since found out that they work best when used with an air pump. The Rio pump is a bad pump and can wipe out a whole tank. I wonder if they still use em?