I have two 820s in my 180. One is in the back left corner pointing toward the front at about a 45 degree angle the other is in the front right corner pointing across the front of the tank. Both of mine are secured using the solid mount not the suction cups. Be sure to place it where it can be easily removed and cleaned. They are great pumps but do require more frequent cleaning than the Maxijets in my experience.

HTH.

-Ed