I'd suggest that you try horse quencher, honestly. It is not a gimick. It does work. Some horses go crazy for it as my big horse, but others are less keen as my oldie, but even he will drink when offered the mix. The point of it is to encourage your horse to drink, and whilst no single way...
Check out the credentials of the chiropractor and if fully registered, contact him/her, discuss the issues and see how you feel. The chiropractor I have to my ex racer is fantastic, an ex vet who moved to chiropractic work because it DOES work. My boy has been better since a series of...