Posted: 12/02/2017 at 16:41
Try brushing them off with a small stiff brush, such as a nail brush etc. A little washing up liquid in water may help with brushing off the waxy fluff. They could also be mealy bugs which look similar - same treatment.
The grapes going mouldy is probably unrelated - better ventilation will help, as will thinning the grapes out on each bunch using vine scissors.
Last edited: 12 February 2017 16:46:36