Working with water can be fun but can also turn out to be just a boring blur. If you like to get the effect I got on this shot, you will need a 10 stop ND Filter, a tripod and a lockable shutter release cable. I use the the Lee Big Stopper. They are expensive but I do recommend get a good one. The problem is that you might get an uneven light with cheaper ones.
This Filter work by darkening down the shot so that the water has time to get really blurry. It looks like a welding glass. Yes it is almost black. Now set your focus, check your exposure without the filter mounted and set your camera to RAW, this is very important. Make sure to use manual focus, your tripod is stable and if you use a dslr, cover your viewfinder otherwise you might get strange color artifacts. This took me a long time to figure out, so make sure covering it.
Now mount the filter then calculate your new exposure. If you want to do it the easy way, download ND Filter Calc on your phone and it will do it for you. Now lock your shutter release cable and wait the calculated amount of time. If it is in the middle of the day you will get a shutter speed at about 40-120 sec at aperture 14. If it is sunset or sunrise you could get up to 10-20 min. Then you might want to consider using the Lee Little Stopper.
You got the shot you are looking for, but it looks blueish. This is why you need RAW-files. When entering your photo software, Capture One in my case, you remove the blue cast by sliding the calvin control to the warm side. In some situations this might not correct the colors the way you like it then the only option is to go black and white. This is very seldom the case but it happens sometimes.
Next step is to mask your water and bring down the clarity to -100. This will give you this metallic feel to the water. If it is not enough, copy your mask and bring down the clarity again. Now color correct the picture as you like it and you are done!
I hope this helped and saved some of your time. It took me quite a while to figure out how to get it as I wanted but in the end it was really simple.