Can I give ACV if I use a nipple water system?

[AccioSarah]

Or will it destroy the nipple waterers?

I've heard you can't use Apple Cider Vinegar with metal...

 

[sfchixn]

For plastic containers (used by most, if not all, nipple waterers) ACV is fine. ACV will corrode the galvanized metal-type waterers.

 

[dirtdoctor]

How much are you feeding them? In a dilution you can use rubber etc... its not going to bother it.