Plastic Containers for milk powder

[knot]

i just keep refilling mine howoften do other people wash it out ?

I used to wash mine out at the end of every day I think (but it has been a few months since DS had formuala so I may well have forgotten )

oh dear am feeling guilty havent washed mine since i split something on it,

I washed them about once a week (eek!). But dd is 2 now and in rude health.