cool deal on the timer issue so the fish will have time to stay out of the jacuzzi yeah it sounds too powerful for the fish and you answered your own question so to say if when the powerhead is on they stay to the other side and when turned off they swim about than they are telling you its too strong i believe AZOO makes a power sweep power head that oscillates and is pretty cool in that size of tank not how much water you have but the actual size being that its a corner tank a powerhead can be a powerful situation as for my 120gal i have a powerhead at each end of the tank and posses no issues that flap your talking about where you can flip it up or down also twists left and right or clockwise or counter clockwise to provide a different direction of flow, good luck buddy..