Washing machine leaking

My hotpoint washing machine which is several years old, recently started leaking but only during the rinse cycle. The water appeared on the floor immediately below the detergent drawer. Taking out the detergent drawer showed a great deal of black slimy mould around and inside the pipe leading to the drum. I put this down to the use of emulsion based conditioner where the oily residue in the pipe attracts mould bacteria over a long period of use. I cleaned the pipe and dertergent drawer using a bottle brush and some dilute acid. I also needed to clean the filter because of all the crud that I'd dislodged. So far there has been no repeat of the leaking.