TRM Epsom SaltsEPSOM SALTS is a feed material for horses containing 100% Pure Magnesium Sulphate Heptahydrate. It should be added to the feed of horses to provide a supplemental source of Magnesium where required, to maintain normal muscle, nerve and gut motility functions. Epsom Salts have also traditionally been utilised externally for bathing and soaking. Instructions for Proper Use: Adult Horses and Large Ponies: Feed 50g per day (approximately 1 scoop