I have 2- 230 Maxspect Gyres on my 48" long 90 gal mixed reef. These gyres can move some water but if you don't want your fish pressed up to the glass just take it down to some of the lower settings. I have them set to just 10% at night and only a ramp up maximum of 50% during the day cycle. My LPS are healthy and happy with full PE at most times. The hammers and Frogspawn get nice back and forth flow on either end of the tank. I really like my maxspect. The newer model controller is apparently easier to work with than the old, but like another comment I have to get out my book OR go to youtube to make changes because I cannot remember the steps right off the top of my head, but could figure it out with tinkering.