Ok, so Im a new pool owner of a used pool. The pool seems to always have real real small trash that my regular and fine net cant get. I think it because the weir in not rising to break the water as the pump is running. Since its always down when the pump turns off all the small trash gets back out to the pool.

If I shut the pump off and lift on the weir, it seems to work and rise and fall to break the water. The minute I turn the pump on it gets slammed to the bottom. It does not seem to have a foam on the back. Is that required or does it have internal springs?