Best way to remove dirt from inside old glass bottles

[pobrew]

Hi all

I'm pretty new to this and have been quite busy, Batch #5 is bubbling away and i have used all my pet and fruit juice bottles. So i managed to get 100 old brown bottles from ebay the other day. I've tried cleaning the inside with a bottle brush but i still have spots of something refusing to leave on lots of the bottles.

Could you advise if there's anything i can soak the bottles in to remove the stubborn buggers or any other ways of removing the dirt (or whatever it is?)

many thanks

Andy

 

[PintOfBitter]

just 3 letters you need to know: PBW. oxiclean in a pinch...
edit: its probaby mold. very common.

 

[GearBeer]

I'd use PBW or OxyClean.

 

[Nurmey]

Welcome to HBT!
Can you buy OxyClean Free there? It really works sweet for soaking crud out of bottles and primaries too. If you can't get it, good old bleach may help you get them clean.