Organic apple cider vinegar can be used as a de-wormer. It will not kill all the worms, but keep them and other parasites at bay. If you have a real infestation you need to figure out what kind they are (sample to the vet) and then get the correct wormer. ACV will also prevent algae from growing in the water. YEA! I give my chickens several options for water though, with and with out the ACV. The dosage is 1 tablespoon per gallon. Do Not put it in a metal container it is bad for the chickens. It will corrode the metal as well. (this also applies to electrolytes)

You need to use organic apple cider vinegar. You need the yeasty chemical at the bottom called the "mother". The ACV that is not "organic" is actually plain white vinegar with carmel coloring. It won't do you any good.