help cleaning sankey spears

[copachono]

hi all, i recently bought some 50L sankey Kegs from due south brewing in miami, i still havent use them since they came pretty dirt, so i wanted to open them and as i thought they were really dirt inside i have manege to clean the keg itself but the spears have some mineral on them and no matter how strong my caustic cleaner its i doesnt clean them so im wondering if anyone have ever clean this type of spear before, its a D style spear from micromatic, probably a few years old but apart from the dirt it seems to be on good shape

 

[Indian_villager]

Look up BLC which can break up beer stone.