The arseholes who did up our flat before selling it to us didn't make the wall in the shower cubicle square before tiling it, so along the back side of the shower there's a gap between the tiles and the tray that starts at ~1cm and diminishes to 0 along the width of the shower tray. Below the height of the tray the gap is filled with expanding foam so no water is getting below the tray, but the foam has been covered with blobby flexi sealant that traps moisture and gets unsightly mould.
I'd like to tidy it up a bit. Would I be better off making a kind of runoff wedge out of grout as in the diagram below, and just closing the join between the grout and the tray with flexible sealant? Or just cover the whole width of the gap more neatly with sealant?
I just need it to be neat for a year or so before we build up the will to have the whole room redone.