i7 Water cooling system

[Jonathan]

i was wondering in order for them to be re-anodised would they need to be taken back to bare metal or can they just be steel wooled then re-anodised?.

Anodising oxidises the outer surface of the part, then the dye bonds with that so to re-anodise and dye you need to remove the previous layer of aluminium oxide. If you submerge it in sodium hydroxide (NaOH / caustic soda) the aluminium oxide layer will be dissolved. However you have to be careful since that will reduce the size of the part, especially if you leave it in too long. If there's fine threads they could disappear...