Tight enough isn't good enough. You should need to move the tensioner a few inches to make it fit, especially if you put a new belt on. I used an 18" breaker bar with the proper socket on the end to move mine. A ratchet of typical length was not adequate to get the torque needed to move it.
Also, if your pulleys and tensioner are original after 11 years, you will want to replace all of them ASAP. At about 68k miles, mine were showing signs of wear. They should not spin so freely that you can get a continuous spin with minimal effort. This indicates the pre-packed grease has dried out. They are cheap insurance and very easy to replace.