OK so it wasn't long before I made another attempt at the slow exposure/long pan. This was taken from the top of cliffs overlooking the Atlantic ocean only 24 hours later but today the weather was misty and grey and the waves were crashing in. I did take a lot at the correct shutter speed to capture the breakers but I think the colours work well in this one.
I am still waiting to try properly with my filters and may start a collection of different oceans with this effect - shame I did not think of this over a year ago as I could have quite a few oceans in my collection by now!