It is quite easy really... many masked layers (manipulating curves [Ctrl+M]) and playing with hues (Ctrl+U). Layered them together to get the final effect I wanted... as it was a fuel dump, I wanted the intense reds to come through, but not a wash.
The rippled effect was created by remote firing (chinese wireless slave triggers) 3 flash units lined up side by side, 1 metre apart, into the reflective foreground and adjusting the metering to fire at -3EV, so that when I push them up again in Photoshop, they will turn out as shadow details/patterns. It was part experimental, not knowing if it will worked when I rigged it up.
But with control PP, it turned out nicer than I thought. So part luck.