Painting in the Southern Hemisphere presents new challenges. The light values are variable. This painting is at Cairns, Australia where the sea really is green! It's humid and the paint takes a bit longer to dry. As a matter of interest, I don't use paint tubes 'in the field', but a small watercolour box and two brushes. One a size 16 and a smaller one for detail, may be a 7. My prefered colours are made by Rowney.
Remeber...no need to use black pen and ink or outline. The adjacent colours give adequate contrast in the finished work.