We have used one of the spray products sold in the grocery stores that has clorox in the formulation....works very well...then after spraying we brush it gently with a small brush w/handle...can be found in nearly every grocery...look in the housewares dept......start with a small amount and begin brushing .....works very well and dries without streaking.......I'll go down and see if I can find the name of the product......It is a scrubbing bubbles product....main name is Fantastic Scrubbing
Bubbles Bleach 5-in 1 all purpose cleaner.....blue spray bottle with green cap....spray on the stains and brush gently..you do not need to rinse this off....good luck! Patrick in paradise !