Ah yes, being a diver I should have realised that reference to fluid in the ear other than the ear canal is probably refering to the eustachian tubes. The easiest way to tell is if when you swallow or move your jaw you *don't* get that popping sound then they are blocked. They basically join the throat to the inner ear and can easily be blocked by a severe cold or flu or other throat problems.

On Christmas Eve I spoke to a friend who wanted to dive the Great Barrier Reef but had some kind of throat problems many years ago and has problem clearing her ears - it took her *ages* to get down to only 12m.

If you do burst an eardrum it's not the end of the world - it takes around 6 weeks before it "heals" and quite a bit longer before you can dive again. I don't think the ear is quite the same again though.

Here's an interesting article:
http://www.american-hearing.org/name/barotrauma.html

Gareth