I have two Gyres on opposite sides of the tank mounted horizontally. Tank is 55" x 26 x 24H. I spent some time googling trying to find information on what people have been doing but there isn't much out there. I found one comment from Coralvue to put them both in random mode and just leave it. I do get a lot of variable flow doing this but it makes the aquarium very loud with the overflow gurgling all the time. Who all has these and what do you find works best for an SPS tank? Also, who else doesn't like the controller? I find it pretty confusing and not straight forward at all (200 series controller). I love the Gyre but hopefully they come out with something a little more intuitive...and also a user guide that is a little easier to understand.