Think, do you really need to use it at all?
Chalk became popular in the late seventies to dry sweat on the pads of climbers fingers. When used in moderation for this purpose it is a brilliant aid to rock climbing. If your route is mostly larger holds or a crack line then chalk won't make much difference.
Most people these days though use it for phycological boost. I haven't used chalk in 2 years, my hands don't sweat now wheras they did when i used it.
I petition chalk be banned.