2003 Subaru Outback Power steering fail after belt change

My car needed news belts so we replaced them. Directly after changing them the power steering makes the noise that is usually indicative of needed power steering fluid.

The power steering is full (up to the line) and nothing seems to be out of order. We tightened the belt and the sound got higher pitched, and then loosened it so the noise was minimal.

The steering is not rough, but the noise is loud. Does the power steering pump need to be "reset" or something? All we did was change the belts.

Any common mistakes or suggestions?
Thanks!