another vote for changing to powder and using fleece liners.
oh and if you have an old blanket made of fleece, you can cut it up into squares to use as liners, it wont need hemming or anything, and will work just as well as ones you buy!

even if you buy a yard of fleece from a shop its cheaper then buying individual liners
you can buy the powder for the nappies and use it just for them until the liquid runs out on other washing. my ds is allergic to bold so we use it for our bedding and clothes, and wash his clothes and nappies separately for now until it runs out. (its a HUGE box..

)