Audio Filters to simulate sound heard underwater

Hello all - Just wondering if anyone out there was aware of an audio filter or a combo of audio filters (preferably that come packaged with FCP 5) and the corresponding parameters and settings needed to simulate an audio track being heard as if one were underwater?

Sounds like you should be able to do it by using a heavy Low Pass filter, EQ and reverb.

Cool - thanks a lot. Any idea as to what range of values I should apply to the Low Pass filter or any of the other ones?

This is assuming you're not trying to hear the sound clearly as dialogue (eg. a water nymph or something). I just did some playing around and this sounds pretty good to my ear:

Low Pass: Frequency 100-300 (depending on how muddy you want it; the lower the number the muddier), Q 0.71

Reverberation: Effect Mix 50, Effect Level 8dB, Brightness -50, Type - Tunnel

Could also add a very small pinch of AUDelay.