Cool waters

This is my first attempt at trying to capture the beauty of nature

with a camera. What shutter speeds are best for flowing water?

Your question was what shutter speeds are best for capturing flowing water.

I assume you're asking about how to best get that silken flowing look. 1/4 seems to have worked well for you here. I usually stick to 1/2 sec or longer. You really need to use a tripod to get the full effect, as it's really hard to hold a camera still that long -- your pulse is enough to shake it.

This photo looks OK as far as the technique, but the composition really isn't that interesting.