I would recommend the opposite. Over washing your hair piece hair is not good for the system. First of all, obviously the hair does not receive the oils it would if you had real hair growing from the scalp. washing further strips the oils and drys out the hair further. I find systems last longer the less you wash them. To me, washing a hair unit twice is over kill. you are better off using a little bit of shampoo and creating a very good lather. It is the lather or suds that does the cleaning.

my 2 cents