'Ruddy 'Ell!

Just tried a background in acrylics on watercolour paper, and found that I couldn't move the paint around how I wanted.  Problem appears to be that compared to Bristol or Illustration board, the paper is so much more absorbant that it literaly sucks the water out of the paint.  Also, even though I sealed the ink drawing with fixative, the ink still ran when water was applied!  The answer appears to be to gesso the surface, so I might try a couple of experiments..